Chess Tactics: Mecking — Rocha, 1969

Here’s the conclusion to another beautiful combination from the early career of Brazilian prodigy Henrique Mecking:

In this game from Mar del Plata 1969, how did he finish off a lovely mating attack?

White to play.

21. ?

Mar del Plata
The coast of Mar del Plata, Argentina. Henrique Mecking tied for third place in this 1969 zonal tournament, as Najdorf and Panno tied for first with a monstrous 15½/18! Source: istockphoto

Another King stuck in the middle