I am reading the book “Combinations in the Middlegame” written by Igor Bondarevsky, Soviet Grandmaster in both over-the-board and correspondence chess, an International Arbiter, a trainer, and an author of chess books. Bondarevsky shared the 1940 Soviet Championship title, and later coached World Champion Boris Spassky. In the Chapter II: Combinational Ideas I found an interesting motif that I didn’t see ( and couldn’t find) anywhere else – seizing a point.
Sacrifice with this motif serves purpose of, as the name says, seizing an important point, then having that point the active side plays some forced line(s).
The first example is from the game Razuvaev-Briem, Puerto-Rico, 1971:
25. Qg5 – this one move threat forces Black to block his King. 25. … Rg8 26. Nd6!
The queen is sacrificed to seize the decisive point. The knight creates the final threat, more exactly triple threat – mate on f7, Nxb7 and Nxc8, there is no defense.
Another example is from the game Fisher-Sofrievsky, Scople, 1967:
The positon of the Black king is weak, it gives an idea to find some tactics to use it. 15. Nd5! The knight is sacrificed to get for the rook square d5. After 15.. exd5 16. Rxd5
16. … Qa6 ( 16. … Qb4 17. a3 ) 17. Rh5 White wins quickly.
In the game Black didn’t accept the sacrifice, played 15. … Rfe8. Then followed 16. Nxe7 Rxe7 17. Rxd6 and White got easily won position.