Game 9:  Botvinnik vs. Tal

0.
@Q0
[Introduction: Spring in Moscow in the 1950's and early '60's. More often than not it meant that Mikhail Botvinnik was playing a match for the World Championship. From 1951 through 1963, Botvinnik contested no less than seven matches for the world title, against the likes of Bronstein, Smyslov, Tal, and Petrosian. Mostly it was as defending champion, but on two occasions, 1958 and 1961, Botvinnik was the Challenger, seeking to regain his crown in a return match. 

We pick up the action in game seven of the 1961 return match. Botvinnik, your partner, has the White pieces in a Nimzo-Indian Defense. Your opponent is the reigning World Champion from Latvia, the fiery Mikhail Tal. Keeping Tal at bay was never an easy task. Once his pieces were active he was a veritable genius at devising attacking ideas. 

But Botvinnik had a plan. "To prepare the sort of openings and middlegame plans associated with them in which the struggle is of a closed nature, the board split into separate sections, the pieces not too mobile. Never mind if objectively my position is worse in that case, at least my opponent will not be able to exploit his swift reaction and memory, and my understanding of chess positions will tell." Sounds good on paper. Still, something is missing. 

Tal, himself, had another explanation for the reversal of fortune. "I was quite unprepared for the change which had taken place in Botvinnik. He arrived for the 1961 match extremely self-disciplined and aggressive, readily going in for a stormy position if it looked favorable for him, which he had not done in 1960." And as regards game seven of the match, "Botvinnik played the whole of this game with youthful energy." 

So, for our current tutorial (game seven of the match), you have the magic formula. Keep the position closed, split the board into separate sections, and don't let the opponent's pieces become active. Above all, play with youthful enthusiasm and have no fear of stormy complications if they appear favorable to your side, especially if they lead to mate.]

1.
@Q1
[{F:W}{B:rnbqkbnr/pppppppp/32/PPPPPPPP/RNBQKBNR WHITE}
{S:c2c4}{D:500}{S:g8f6}{D:500}{S:b1c3}{D:500}{S:e7e6}{D:500}{S:d2d4}{D:500}
{S:f8b4}{D:500}{S:a2a3}{D:500}{S:b4c3}{D:500}{S:b2c3}{D:500}{S:b7b6}{D:500}
{S:f2f3}{D:500}{S:c8a6}{D:500}{S:e2e4}{D:500}{S:d7d5}{D:500}{S:c4d5}{D:500}
{S:a6f1}
{QM:Select White's 9th move.;
9. dxe6:Incorrect. The correct answer was Kxf1.:-3;
9. Kxf1:Correct.:2}]

2.
@Q2
[{R}{D:1000}{S:e1f1}{A:We1f1}{D:1000}{S:e6d5}{A:Be6d5}{D:2000}{R}
{QM:Select White's 10th move.;
10. Qa4+:Incorrect. The correct answer was Bg5.:2;
10. Ra2:Incorrect. The correct answer was Bg5.:1;
10. Qc2:Incorrect. The correct answer was Bg5.:2;
10. c4:Incorrect. The correct answer was Bg5.:-1;
10. Qd3:Incorrect. The correct answer was Bg5.:2;
10. exd5:Incorrect. The correct answer was Bg5.:2;
10. e5:Incorrect. The correct answer was Bg5.:3;
10. Qe2:Incorrect. The correct answer was Bg5.:2;
10. Bg5:Correct.:4;
10. g4:Incorrect. The correct answer was Bg5.:1;
10. Nh3:Incorrect. The correct answer was Bg5.:2}]

3.
@Q3
[{R}{D:1000}{S:c1g5}{A:Wc1g5}{D:1000}{S:h7h6}{A:Bh7h6}{D:2000}{R}
{QM:Select White's 11th move.;
11. Qa4+:Correct.:4;
11. Bc1:Incorrect. The correct answer was Qa4+.:-1;
11. Bd2:Incorrect. The correct answer was Qa4+.:-1;
11. Be3:Incorrect. The correct answer was Qa4+.:-1;
11. e5:Incorrect. The correct answer was Qa4+.:-1;
11. Bf4:Incorrect. The correct answer was Qa4+.:2;
11. Bxf6:Incorrect. The correct answer was Qa4+.:3;
11. Bh4:Incorrect. The correct answer was Qa4+.:2}]

4.
@Q4
[{R}{D:1000}{S:d1a4}{A:Wd1a4}{D:1000}{S:c7c6}{A:Bc7c6}{D:2000}{R}
{QM:Select White's 12th move.;
12. exd5:Incorrect. The correct answer was Bh4.:-2;
12. e5:Incorrect. The correct answer was Bh4.:-1;
12. Bxf6:Incorrect. The correct answer was Bh4.:3;
12. Bf4:Incorrect. The correct answer was Bh4.:1;
12. Bh4:Correct.:5}]

5.
@Q5
[{R}{D:1000}{S:g5h4}{A:Wg5h4}{D:1000}{S:d5e4}{A:Bd5e4}{D:2000}{R}
{QM:Select White's 13th move.;
13. d5:Incorrect. The correct answer was Re1.:-1;
13. Re1:Correct.:4;
13. fxe4:Incorrect. The correct answer was Re1.:1;
13. Bxf6:Incorrect. The correct answer was Re1.:2;
13. Bg3:Incorrect. The correct answer was Re1.:1}]

6.
@Q6
[{R}{D:1000}{S:a1e1}{A:Wa1e1}{D:1000}{S:g7g5}{A:Bg7g5}{D:2000}{R}
{QM:Select White's 14th move.;
14. fxe4:Incorrect. The correct answer was Bf2.:-2;
14. Bf2:Correct.:5;
14. Bg3:Incorrect. The correct answer was Bf2.:2}]

7.
@Q7
[{R}{D:1000}{S:h4f2}{A:Wh4f2}{D:1000}{S:d8e7}{A:Bd8e7}{D:2000}{R}
{QM:Select White's 15th move.;
15. c4:Incorrect. The correct answer was Ne2.:1;
15. Qc2:Incorrect. The correct answer was Ne2.:2;
15. fxe4:Incorrect. The correct answer was Ne2.:2;
15. Ne2:Correct.:5;
15. h4:Incorrect. The correct answer was Ne2.:2}]

8.
@Q8
[{R}{D:1000}{S:g1e2}{A:Wg1e2}{D:1000}{S:b6b5}{A:Bb6b5}{D:2000}{R}
{QM:Select White's 16th move.;
16. Qa5:Incorrect. The correct answer was Qc2.:2;
16. Qb4:Incorrect. The correct answer was Qc2.:1;
16. Qb3:Incorrect. The correct answer was Qc2.:2;
16. Qc2:Correct.:4;
16. Qd1:Incorrect. The correct answer was Qc2.:1}]

9.
@Q9
[{R}{D:1000}{S:a4c2}{A:Wa4c2}{D:1000}{S:e7a3}{A:Be7a3}{D:2000}{R}
{QM:Select White's 17th move.;
17. fxe4:Incorrect. The correct answer was h4.:3;
17. Ng3:Incorrect. The correct answer was h4.:3;
17. h4:Correct.:5}]

10.
@Q10
[{R}{D:1000}{S:h2h4}{A:Wh2h4}{D:1000}{S:g5h4}{A:Bg5h4}{D:2000}{R}
{QM:Select White's 18th move.;
18. fxe4:Incorrect. The correct answer was Bxh4.:2;
18. Nf4:Incorrect. The correct answer was Bxh4.:1;
18. Bxh4:Correct.:3;
18. Rxh4:Incorrect. The correct answer was Bxh4.:2}]

11.
@Q11
[{R}{D:1000}{S:f2h4}{A:Wf2h4}{D:1000}{S:b8d7}{A:Bb8d7}{D:2000}{R}
{QM:Select White's 19th move.;
19. fxe4:Incorrect. The correct answer was Ng3.:2;
19. Bxf6:Incorrect. The correct answer was Ng3.:1;
19. Kf2:Incorrect. The correct answer was Ng3.:1;
19. Nf4:Incorrect. The correct answer was Ng3.:1;
19. Ng3:Correct.:4}]

12.
@Q12
[{R}{D:1000}{S:e2g3}{A:We2g3}{D:1000}{S:e8c8}{A:Be8c8}{S:a8d8}{A:Ba8d8}{D:2000}{R}
{QM:Select White's 20th move.;
20. fxe4:Incorrect. The correct answer was Nxe4.:3;
20. Nxe4:Correct.:4;
20. Bxf6:Incorrect. The correct answer was Nxe4.:1;
20. Kf2:Incorrect. The correct answer was Nxe4.:-1;
20. Nf5:Incorrect. The correct answer was Nxe4.:-1}]

13.
@Q13
[{R}{D:1000}{S:g3e4}{A:Wg3e4}{D:1000}{S:h8e8}{A:Bh8e8}{D:2000}{R}
{QM:Select White's 21st move.;
21. Nxf6:Incorrect. The correct answer was Kf2.:3;
21. Bxf6:Incorrect. The correct answer was Kf2.:3;
21. Kf2:Correct.:5;
21. Bg3:Incorrect. The correct answer was Kf2.:2}]

14.
@Q14
[{R}{D:1000}{S:f1f2}{A:Wf1f2}{D:1000}{S:f6e4}{A:Bf6e4}{D:2000}{R}
{QM:Select White's 22nd move.;
22. Qxe4:Incorrect. The correct answer was fxe4.:-3;
22. Rxe4:Incorrect. The correct answer was fxe4.:1;
22. fxe4:Correct.:3}]

15.
@Q15
[{R}{D:1000}{S:f3e4}{A:Wf3e4}{D:1000}{S:f7f6}{A:Bf7f6}{D:2000}{R}
{QM:Select White's 23rd move.;
23. Ra1:Correct.:4;
23. d5:Incorrect. The correct answer was Ra1.:1;
23. e5:Incorrect. The correct answer was Ra1.:1;
23. Bg3:Incorrect. The correct answer was Ra1.:2}]

16.
@Q16
[{R}{D:1000}{S:e1a1}{A:We1a1}{D:1000}{S:a3e7}{A:Ba3e7}{D:2000}{R}
{QM:Select White's 24th move.;
24. Rxa7:Correct.:3;
24. Qa2:Incorrect. The correct answer was Rxa7.:1;
24. d5:Incorrect. The correct answer was Rxa7.:1;
24. e5:Incorrect. The correct answer was Rxa7.:1;
24. Rhe1:Incorrect. The correct answer was Rxa7.:1;
24. Kf3:Incorrect. The correct answer was Rxa7.:1;
24. Bg3:Incorrect. The correct answer was Rxa7.:1}]

17.
@Q17
[{R}{D:1000}{S:a1a7}{A:Wa1a7}{D:1000}{S:e7e4}{A:Be7e4}{D:2000}{R}
{QM:Select White's 25th move.;
25. Ra8+:Incorrect. The correct answer was Qxe4.:3;
25. Qd2:Incorrect. The correct answer was Qxe4.:1;
25. Qd1:Incorrect. The correct answer was Qxe4.:1;
25. Qxe4:Correct.:3}]

18.
@Q18
[{R}{D:1000}{S:c2e4}{A:Wc2e4}{D:1000}{S:e8e4}{A:Be8e4}{D:2000}{R}
{QM:Select White's 26th move.;
26. Ra8+:Correct.:4;
26. Rha1:Incorrect. The correct answer was Ra8+.:-2;
26. Kf3:Incorrect. The correct answer was Ra8+.:1;
26. Bg3:Incorrect. The correct answer was Ra8+.:2}]

19.
@Q19
[{R}{D:1000}{S:a7a8}{A:Wa7a8}{D:1000}{S:d7b8}{A:Bd7b8}{D:2000}{R}
{QM:Select White's 27th move.;
27. Ra7:Incorrect. The correct answer was Bg3.:1;
27. Re1:Incorrect. The correct answer was Bg3.:-2;
27. Kf3:Incorrect. The correct answer was Bg3.:1;
27. Bxf6:Incorrect. The correct answer was Bg3.:-2;
27. Bg3:Correct.:4}]

20.
@Q20
[{R}{D:1000}{S:h4g3}{A:Wh4g3}{D:1000}{S:c8b7}{A:Bc8b7}{D:2000}{R}
{QM:Select White's 28th move.;
28. R8a2:Incorrect. The correct answer was Rha1.:1;
28. Rha1:Correct.:4;
28. Rxb8+:Incorrect. The correct answer was Rha1.:2;
28. Bxb8:Incorrect. The correct answer was Rha1.:-2;
28. Kf3:Incorrect. The correct answer was Rha1.:2;
28. Rxh6:Incorrect. The correct answer was Rha1.:-3}]

21.
@Q21
[{R}{D:1000}{S:h1a1}{A:Wh1a1}{D:1000}{S:d8c8}{A:Bd8c8}{D:2000}{R}
{QM:Select White's 29th move.;
29. R8a7+:Correct.:4;
29. R1a7+:Incorrect. The correct answer was R8a7+.:2;
29. Bxb8:Incorrect. The correct answer was R8a7+.:2;
29. Rxb8+:Incorrect. The correct answer was R8a7+.:1;
29. Bd6:Incorrect. The correct answer was R8a7+.:3;
29. Kf3:Incorrect. The correct answer was R8a7+.:2}]

22.
@Q22
[{R}{D:1000}{S:a8a7}{A:Wa8a7}{D:1000}{S:b7b6}{A:Bb7b6}{D:2000}{R}
{QM:Select White's 30th move.;
30. R7a6+:Incorrect. The correct answer was Bxb8.:-3;
30. R1a6+:Incorrect. The correct answer was Bxb8.:-3;
30. Bxb8:Correct.:4;
30. Bd6:Incorrect. The correct answer was Bxb8.:3;
30. Rf7:Incorrect. The correct answer was Bxb8.:2;
30. Rh7:Incorrect. The correct answer was Bxb8.:2}]

23.
@Q23
[{R}{D:1000}{S:g3b8}{A:Wg3b8}{D:1000}{S:b5b4}{A:Bb5b4}{D:2000}{R}
{QM:Select White's 31st move.;
31. R7a6+:Incorrect. The correct answer was Bd6.:1;
31. R1a6+:Incorrect. The correct answer was Bd6.:1;
31. Ra8:Incorrect. The correct answer was Bd6.:1;
31. cxb4:Incorrect. The correct answer was Bd6.:-2;
31. Bc7+:Incorrect. The correct answer was Bd6.:2;
31. c4:Incorrect. The correct answer was Bd6.:2;
31. Bd6:Correct.:4;
31. Bg3:Incorrect. The correct answer was Bd6.:1}]

24.
@Q24
[{R}{D:1000}{S:b8d6}{A:Wb8d6}{D:1000}{S:b4c3}{A:Bb4c3}{D:2000}{R}
{QM:Select White's 32nd move.;
32. R7a6+:Incorrect. The correct answer was Bc5+.:1;
32. R1a6+:Incorrect. The correct answer was Bc5+.:1;
32. R1a5:Incorrect. The correct answer was Bc5+.:1;
32. Rb1+:Incorrect. The correct answer was Bc5+.:-3;
32. Bc5+:Correct.:4}]

25.
@Q25
[{R}{D:1000}{S:d6c5}{A:Wd6c5}{D:1000}{S:b6b5}{A:Bb6b5}{D:2000}{R}
{QM:Select White's 33rd move.;
33. R7a5+:Incorrect. The correct answer was R1a4.:1;
33. R1a5+:Incorrect. The correct answer was R1a4.:1;
33. R7a4:Incorrect. The correct answer was R1a4.:3;
33. R1a4:Correct.:5;
33. Rb1+:Incorrect. The correct answer was R1a4.:1;
33. Rb7+:Incorrect. The correct answer was R1a4.:1;
33. Rc1:Incorrect. The correct answer was R1a4.:1}]

0.
@Q26
[BONUS QUESTIONS]

Bonus Questions
27.
@Q27
[{F:B}{B:rn1qk2r/p1p2pp1/1p3n1p/3p2B1/3PP3/P1P2P2/6PP/R2Q1KNR BLACK}
{R}{D:1000}{S:g5f6}{A:Wg5f6}{D:2000}{R}
{QM:Bonus Question 1. 
After 11. Bxf6, how should Black take back?;
11...Qxf6:Correct. Developing a new piece is the way to go. True, White can win a pawn by 12. exd5, but after 12...0-0 13. Ne2 c6 14. dxc6 Nxc6, Black has full compensation. He has a lead in development, an open board to play with, and an uncastled White king to aim at.:1;
11...gxf6:Incorrect. This avoids loss of the d-pawn, 12. exd5? Qxd5, but it rips up Black's kingside. The square f5 in particular looks like a good place to sink a White knight, Ne2-g3-f5.:0}]

28.
@Q28
[{F:W}{B:rn1qk2r/p1p2pp1/1p3n1p/3p2B1/Q2PP3/P1P2P2/6PP/R4KNR WHITE}
{R}{D:1000}{S:d8d7}{A:Bd8d7}{D:1000}{R}{S:a4d7}{A:Wa4d7}{D:1000}{R}{S:b8d7}{A:Bb8d7}{D:2000}{R}
{VB:Bonus Question 2. 
After the queen interposition, 11...Qd7, and the trade of queens, 12. Qxd7+ Nbxd7, how should White continue? Give his next move.;g5f6;Correct. After 13...Nxf6, then 14. e5 yields White some positional advantage. How much is hard to say. Psychologically, Botvinnik would have a big edge. He gets a quiet, technical position where strategy predominates. That's his forte. Tal, who revels in complex piece-play, would have little chance for activity, and his game would be thrown off.:1;{R}{B:r3k2r/p1pn1pp1/1p3n1p/3p2B1/3PP3/P1P2P2/6PP/R4KNR}{A:Wg5f6}{S:g5f6}Incorrect. White should continue with Bxf6.}]

29.
@Q29
[{F:B}{B:rn1qk2r/p4pp1/1pp2n1p/8/Q2Pp2B/P1P2P2/6PP/R4KNR BLACK}
{R}{D:1000}{S:f3e4}{A:Wf3e4}{D:2000}{R}
{VB:Bonus Question 3. 
How does Black continue after 13. fxe4? Give his next move.;g7g5;Correct. 13...g5 14. Bg3 Nxe4 appears playable. If 15. Re1, then 15...f5. And if instead 15. Bxb8, then 15...Qf6+! (to guard c6) followed by 16...Rxb8. In the game Botvinnik had a simple solution, 13. Re1, pinning the e4-pawn, so it couldn't run away. He took it later on.:2;{R}{B:rn1qk2r/p4pp1/1pp2n1p/8/Q2PP2B/P1P5/6PP/R4KNR}{A:Bg7g5}{S:g7g5}Incorrect. Black should continue with g5.}]

30.
@Q30
[{F:B}{B:rn1qk2r/p4p2/1pp2n1p/6p1/Q2Pp2B/P1P2P2/6PP/4RKNR BLACK}
{R}{D:1000}{S:h4g3}{A:Wh4g3}{D:2000}{R}
{VB:Bonus Question 4. 
If White retreats 14. Bg3 (instead of 14. Bf2), what would Black play? Give his 14th move.;d8d5;Correct. The main feature is that Black's queen cannot easily be driven off by 15. c4, because the d4-pawn would then be hanging, 15...Qxd4. This is why Botvinnik preferred 14. Bf2, which protects the d4-pawn. So 14...Qd5 could then be answered by 15. c4.:2;{R}{B:rn1qk2r/p4p2/1pp2n1p/6p1/Q2Pp3/P1P2PB1/6PP/4RKNR}{A:Bd8d5}{S:d8d5}Incorrect. Black should play Qd5.}]

31.
@Q31
[{F:B}{B:rn2k2r/p3qp2/1pp2n1p/6p1/Q2Pp3/P1P2P2/5BPP/4RKNR BLACK}
{R}{D:1000}{S:f3e4}{A:Wf3e4}{D:1000}{R}{S:f6e4}{A:Bf6e4}{D:1000}{R}{S:a4c2}{A:Wa4c2}{D:1000}{R}{S:f7f5}{A:Bf7f5}{D:1000}{R}{S:g2g4}{A:Wg2g4}{D:2000}{R}
{VB:Bonus Question 5. 
How does Black play after 15. fxe4 Nxe4 16. Qc2 f5 17. g4? Give his next move.;b8d7;Correct. The continuation 18. gxf5 Ndf6 is sufficient to maintain balance.:2;{R}{B:rn2k2r/p3q3/1pp4p/5pp1/3Pn1P1/P1P5/2Q2B1P/4RKNR}{A:Bb8d7}{S:b8d7}Incorrect. Black should play Nd7.}]

32.
@Q32
[{F:W}{B:rn2k2r/p3qp2/2p2n1p/1p4p1/3Pp3/P1P2P2/2Q1NBPP/4RK1R WHITE}
{R}{D:1000}{S:e4f3}{A:Be4f3}{D:2000}{R}
{VB:Bonus Question 6. 
How does White answer 16...exf3? Give his next move.;e2g3;Correct. This wins the queen and looks pretty good.:1;{R}{B:rn2k2r/p3qp2/2p2n1p/1p4p1/3P4/P1P2p2/2Q1NBPP/4RK1R}{A:We2g3}{S:e2g3}Incorrect. White should answer with Ng3.}]

33.
@Q33
[{F:W}{B:2kr3r/p2n1p2/2p2n1p/1p6/3PN2B/q1P2P2/2Q3P1/4RK1R WHITE}
{R}{D:1000}{S:f6e4}{A:Bf6e4}{D:2000}{R}
{VB:Bonus Question 7. 
If Black plays 20...Nxe4, what is White's best capture? Give his next move.;c2e4;Correct. This threatens 22. Qxc6+ as well as 22. Bxd8. Note that 21. Bxd8 allows 21...Ng3+.:1;{R}{B:2kr3r/p2n1p2/2p4p/1p6/3Pn2B/q1P2P2/2Q3P1/4RK1R}{A:Wc2e4}{S:c2e4}Incorrect. White's best capture is by Qxe4.}]

34.
@Q34
[{F:B}{B:2krr3/p2n1p2/2p2n1p/1p6/3PN2B/q1P2P2/2Q3P1/4RK1R BLACK}
{R}{D:1000}{S:e4f6}{A:We4f6}{D:2000}{R}
{VB:Bonus Question 8. 
Why didn't White play 21. Nxf6? Give Black's next move.;e8e1;Correct. 22. Kxe1 Qa1+ 23. Qd1 Qxc3+ 24. Kf1 Ne5! and suddenly the game has become rather complicated. This is not the sort of position you want to play against Tal. So rather than give Tal the attack, Botvinnik preferred 21. Kf2! connecting his rooks, and going over to the attack himself.:2;{R}{B:2krr3/p2n1p2/2p2N1p/1p6/3P3B/q1P2P2/2Q3P1/4RK1R}{A:Be8e1}{S:e8e1}Incorrect. Black then would play Rxe1+.}]

35.
@Q35
[{F:W}{B:R1kr4/3n4/2p2p1p/1p6/3Pr2B/2P5/5KP1/7R WHITE}
{R}{D:1000}{S:c8c7}{A:Bc8c7}{D:2000}{R}
{VB:Bonus Question 9. 
How does White answer 26...Kc7? Give his next move.;h4g3;Correct. This wins at least a knight.:1;{R}{B:R2r4/2kn4/2p2p1p/1p6/3Pr2B/2P5/5KP1/7R}{A:Wh4g3}{S:h4g3}Incorrect. White should answer with Bg3+.}]

36.
@Q36
[{F:W}{B:Rn1r4/1k6/2p2p1p/1p6/3Pr3/2P3B1/5KP1/R7 WHITE}
{R}
{VB:Bonus Question 10. 
What is White threatening to play?;a1a7;Correct. It is mate after 29...Kb6 30. Bc7# or 29...Kc8 30. Rc7#. This is why Tal played 28...Rc8, to cover the c7-point. But it wasn't enough.:1;{R}{B:Rn1r4/1k6/2p2p1p/1p6/3Pr3/2P3B1/5KP1/R7}{A:Wa1a7}{S:a1a7}Incorrect. White is threatening to play R1a7+.}]

37.
@Q37
[{F:W}{B:1Br5/R7/1kp2p1p/1p6/3Pr3/2P5/5KP1/R7 WHITE}
{R}{D:1000}{S:c8b8}{A:Bc8b8}{D:2000}{R}
{VB:Bonus Question 11. 
If Black takes back, 30...Rxb8, what move does White play?;a1a6;Correct. The principle says to always play mate-in-one move, if you have it.:1;{R}{B:1r6/R7/1kp2p1p/1p6/3Pr3/2P5/5KP1/R7}{A:Wa1a6}{S:a1a6}Incorrect. White should then play R1a6# checkmate.}]

38.
@Q38
[Conclusion: Botvinnik selects the uncompromising Samisch variation of the Nimzo-Indian Defense. At the cost of a tempo, 4. a3, and doubled c-pawns, he obtains the two bishops and a broad pawn center. To avoid Botvinnik's opening preparation, Tal slides into an obscure side line (moves 4-7) designed to trade off one of the White bishops (the light-square one), but also allowing White to undouble his c-pawns. It turns out that Botvinnik was prepared even for this unlikely contingency. His 10th and 11th moves both smack of the midnight oil. Certainly this was Tal's impression.  

The critical fight for control of the center takes place over four densely packed moves, (12-16). At the end of the sequence, Tal, realizing that he's getting outgunned in the center, grabs the undefended a3-pawn. This at least gives Black an extra pawn for his troubles elsewhere. 

And troubles mount after the weak pawn capture, at move seventeen, 17...gxh4 (17...Rg8 was in order). Botvinnik holds the upperhand both in the center and on the kingside. In fact, Tal's position starts to look desperate. Tal finally gets his king out of the center on the 19th move (19...0-0-0), and on move twenty (20...Rhe8), he offers Botvinnik a chance to win a piece. Taking the knight, 21. Nxf6, would lead to messy complications after 21...Rxe1+ 22. Kxe1 Qa1+ 23. Qd1 Qxc3+ 24. Kf1 Ne5!. So Botvinnik declined the offer (21. Kf2!), and went over to the attack himself, 23. Ra1 and 24. Rxa7. Now it was Tal's king that was facing danger. 

The trade of queens at move twenty-five in no way lessened the force of White's attack. Soon Tal had to shed a piece, 30. Bxb8, and at the end, Botvinnik had placed the Black king in a mating net. 

Botvinnik went on to win the match handsomely, 10 wins, five losses, 6 draws. It was Botvinnik's last victory in a World Championship Match. Two years later he lost the title to Tigran Petrosian. By then the return match clause had been eliminated and Botvinnik, the old warrior, decided to drop out of the championship cycle. He had his turn. The future belonged to the younger generation, guys like Petrosian, Spassky, and Fischer.]