In 1966 and 1969 Tigran Petrosian and Boris Spassky contested two epic battles for the world crown. In the first of these Petrosian became the only world champion to actually win a title defence for 32 years when his inspired defensive technique thwarted all of Spassky's aggressive intentions. In the second of these two ferocious fights Spassky eventually broke through to seize the world title. En route the two great players created some of the most beautiful chess ever witnessed at this high level, sparkling with numerous sacrifices of rook for bishop or knight, piece sacrifices to inaugurate enduring attacks and even a stunning queen sacrifice by Petrosian in game 10 of the first encounter.