A Touch of Jujitsu
Petrosian was a genius! How else could he cause a player as eminent as Korchnoi to suddenly collapse? He brings about a position where his opponent's pieces rely on each other for support. Then with the skill of a jujitsu expert, he applies pressure at the critical points, and Korchnoi is forced to resign.
(notes & title by irving chernev)
and...an EPIC-LY HARD CHESS PROBLEM: