Illustration: Portisch-Kasparov, 1981
Black to play:
1...? Here a young Garry Kasparov is two pawns behind and Portisch is on his way to promote the d6 pawn. Garry uncorked a combination which saves the day and the half point.
1.. Rd2! 2.Qd2 Qf3+ 3.Qg2 Ng3+! ( The point) 4 hg3.
Let's see the position reached on the next diagram
Portisch-Kasparov 1981 after 4 hg3
Black to play
Here, Kasparov can force the perpetual.
4..Qh5+ 5Qh2 Qf3+ 6 Rg2 Qd1+ 7 Qg1 Qh5+
8 Rh2 Qf3+
Despite being an entire rook up, White cannot escape checks from the Queen.
The perpetual check resource is a very important drawing motif.
Exercise: Miles-Rachels 1989
Black to play and draw
1...?
