The knight was well placed on c5, supporting the a4-push on the queenside. However, Black was planning ...Ke7, unpinning the knight and offering a rook trade next. With this knight maneuver, Kramnik looks for the e5-square and another weakness like g6 besides threatening Nb4. The knight invasion on e5 is devastating.
Black cannot move the knight since after the rook trade, the bishop on f7 is hanging.
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Ian Nepomniachtchi Liren Ding World-ch 2023 White to move
Black has just played 31...Rb8 from a8, in order to avoid being captured with the e4-queen. This move looks inoffensive but Black has some ideas in mind. What is the best move for White here?
Fantastic prophylaxis from Nepo. White stops b4 by protecting the b2-pawn and now is ready to start the attack on the kingside.
32.g4 looks natural but allows Black counterplay after 32...b4! 33.Qc4 The point after 33.cxb4 is that the b2-pawn is hanging! 33...bxc3 and Black has decent chances of drawing the game since all the pawns on the queenside have disappeared.
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Nigel Short Garry Kasparov Amsterdam 1996 White to move
A classic example of prophylaxis. With his next moves White restricts the black minor pieces, guaranteeing to keep the bishop pair as well.
Stopping ...Bc5 and fixing the black pawn structure on the queenside. White can put a lot of pressure on in the future with an eventual a4.