Kg2 gets him out of trouble, but Black has a zwischenzug:

The earliest known use of the term zwischenzug did not occur until after all of these games.

The opponent cannot choose to defend the other piece, or use a zwischenzug to complicate the situation.

The near ubiquity of the zwischenzug makes long combinations all the more rare and impressive.

No one knows when the first zwischenzug was played, but it was evident long before the term itself existed.

As with any fairly common chess tactic, it is impossible to pinpoint when the first zwischenzug was played.

The effect of a zwischenzug is to change the status quo before a tactic can come to fruition.

The concept of a zwischenzug is often listed as a tactic, but might properly be called a counter-tactic instead.

Morphy, the strongest player of the day, instead played the zwischenzug 10...Qh4!

That's the essence of "zwischenzug" in chess.

However, White has a zwischenzug:

(An astonishing "zwischenzug" that probably escaped Gulko's attention.

Another prominent example that brought the concept of zwischenzug, albeit not the term itself, to public attention was Tartakower-Capablanca, New York 1924.

A zwischenzug occurred in Mieses-Reshevsky, Margate 1935.

Ideally, the zwischenzug changes the situation to the player's advantage, such as by gaining material or avoiding what would otherwise be a strong continuation for the opponent.

In chess, zwischenzug (German for in-between move) means playing a move that ignores the opponent's move temporarily to create a new threat.

However, Capablanca sprang the zwischenzug 9...Nd5!

Bxe4, which would have given Anand the opportunity to fix his queenside pawn weaknesses with 21...axb6, Carlsen played the zwischenzug 21.

An unexpected check in a forced combination or an overlooked cross-check in a planned series of checks may serve as sort of a zwischenzug, foiling the plan.

Qg1 Nxe5, De Vere's zwischenzug had netted him two more pawns, leaving him with the material advantage of four pawns for a knight.

A forked piece such as the queen might check the enemy king, a zwischenzug, giving time to move the second forked piece to safety on the next move.

The first known use of the term zwischenzug, however, did not occur until 1933, when the prolific American chess authors Fred Reinfeld and Irving Chernev used it in their book Chess Strategy and Tactics.