[Note: Add 23 to the diagram's move numbers--chess.com misnumbered them.]
24.Kf1 - Centralizing his king.
24...Ne4! - There's a tactical threat here! If White doesn't respond accurately, 25...Nc3! 26.a4 Nb3! 27.a4 Nc3! 28.a5 Na2! wins a pawn and likely the game. It's the same tactic we learned in Chekhover, 1938.
25.a3! - Accurate.
25...Ke7 26.Ke2 - More centralization.
26...c5 27.bxc5 Nxc5 - This swap slightly favors Black, because he's closer to creating a passed pawn on the queenside.
28.Nd4 g6 29.f3 a6 - Nd4 wasn't particularly threatening, but both sides decide to minimize counterplay. Now White's knight has no potential penetration points, and the Black's knight only option is the silly a4.
29.g4 Kd6 30.h4 Kd5 31.Kd2 - While White attempts to create a passer on the kingside, Black centralizes his king. Soon Black's king is superior and White's on the defensive.
31...Ne6! 32. Nb3! Offering a knight exchange. Black's king is superior to White's king, and knight endings are easier to draw than pawn endings. Don't get too hung up on Botvinnik's Rule! White wisely declines the offer.
33...f5 34.gxf5 gxf5 35.Kc3 b5?! - This seems like a mistake. It moves Black's pawns closer to White's king. White will easily penetrate on the queenside, but Black will have trouble penetrating on the kingside. f4? is met by e4! I think Black had winning chances before this.
36.Kb4 Nd8!? - This seems odd when a simple Nc7 defends the pawns, but Nc7 is too passive, and there's an idea behind this move we'll soon see.
37.Ka5 Kc4 38.Nd4 f4! - Excellent timing! Now e4 and fxe4 are impossible.
39. Nf5 fxe3 40. Nxe3+ Kd3 41. Nf5 Nc6+ 42. Kxa6 b4! 43. axb4 Nxb4+ - White's a pawn up, but Black's king is more active. Botvinnik forecasts a draw.
44. Kb5 Nc2 45. Kc5 Ke2 46. Nxh6 Kxf3 - Finally! Knight & Pawn vs Knight. Now Botvinnik's Rule again forecasts a win, but concrete calculation shows it's only a draw. White's own knight tragically slows his own pawn's advance.
47. h5 Kf4 48. Nf7 Kf5 49. Kd6 Kf6 50. Ne5 Kg5 1/2-1/2
An interesting game. Certainly not a boring "Grandmaster Draw". :)