Continuing the game with Taimanov's commentary:—

10.Rc1
The move 10.b4 has been frequently tested here, however I rejected it as superfluous to the scheme I had prepared.
10...f5








This position was already essayed in our first game of the match. There I played 11.exf5 and then 11...gxf5 12.Ng5 h6 13.Ne6 Bxe6 14.dxe6 Qc8 15.Qb3 c6 led to a double-edged position with mutual chances. That game proceeded fascinatingly, the scales inclined to one side then the other several times. I was the last to make a mistake in time trouble and lost the game, but it was obvious that the opening conversation had not been exhausted, and that the discussion would be continued. So, it happened.
11.Qb3!?
My innovation comes first! This follows my preparation for the duel! The main idea from the first game remains: transfer the knight to e6 followed by opening the center, but the text sharply enlivens the tactical set-up. The Queen from b3 'X-rays' the Black King, and simultaneously 'looks' at the b7-pawn, which could be vulnerable to capture after an eventual exchange of the bishop for the e6-knight. The theoretical dispute with Fischer has found a new impulse!
11...b6
Fischer thought on this reply for a long time (which testifies to the advantage obtained by his opponent's home preparation) and probably came to the conclusion of the necessity of first stopping the advance c4-c5, which promotes White's chances to open the strategically important c-file. Subsequently analysts put forward alternative ideas of merit - 11. f4 (I. Boleslavsky) and 11... Kh8 (M. Tal).
12.exf5 gxf5
It is always basic with Fischer. With 12... Nxf5 or 12... Bxf5, White's possession of the outpost e4 ensures a stable positional advantage.
13.Ng5
The general plan in operation – the knight is aiming at e6.








13...Nf6
In case of 13...h6 14.Ne6 Bxe6 15.dxe6 Qc8 (or 15...c6 16.Bh5!) a highly advantageous continuation for White is 16.Nd5 Qxe6 17.Nxe7+ Qxe7 18.c5+ Kh8 19.cxd6 Nxd6 (or 19...cxd6 20.Rfd1) 20.Rc6!, confirmed by my game with M. Tseitlin played two years later.
14.f4!
An important part of the preconceived plan, whose value Fischer apparently underestimated...
14...h6
Fischer trusts in the reliability of Black's formation and bravely enters uncompromising conflict. More circumspect, but also more "yielding" would have been 14...e4. However in this case White gains obvious positional advantages by way of 15.Nd1 h6 16.Nh3 followed by Ne3, Nf2 and Bc3. Such conformism is alien to Fischer and he never opted for such passive continuations.
15.fxe5! dxe5








Certainly Fischer must not have liked the continuation 15...hxg5 16.exf6 Bxf6 17.Bh5.
16.c5!
But I think this blow turned out to be an unexpected and distressing surprise for Fischer. The battery of white pieces has come into action! However, had I been in a less martial mood, I might have contented myself with the quiet 16.Nf3, maintaining White's doubtless positional plusses.
16...Nfxd5
It is obvious that the alternative 16...hxg5 17.d6+ Kh8 18.dxe7 Qxe7 19.cxb6 axb6 20.Bxg5 was quite unattractive, as well as the reply 16...Kh8 in view of 17.d6!
Hand-to-hand fighting begins where courageous imagination, exact calculation and ... strong nerves are required. By the way, in this game, nerves "played pranks" on both players. I remember, at one moment of the duel, when I rose from the table after making a move, and by customary habit, walked on the stage. Fischer, having his meditation interrupted unexpectedly, turned to the chief arbiter Bozhidar Kazhic, through his "charge' d'affaires" Ed. Edmondson, with the complaint that my walking disturbed him. Kazhic delicately related this to me, adding that from his perspective he could not support Fischer's claim as it was my right to walk on my own side of the stage. But not wishing such a conflict, I offered a gentlemen's compromise - if Bobby for his part would desist from his habit of beating out "a tattoo with his legs" under the table, I would abandon my walking on the stage... Fischer agreed, a consensus was found...
But let us return to the game, which had entered a most dramatic phase.