Why did Petrosian stop playing the Petroff

At the halfway mark in the 1969 World Championship between Petrosian and Spassky, the match score was level. Petrosian only needed to draw the match to retain his title, and with his super-solid Petroff it looked like he was going to wrap things up. But in game 17 and 19 Petrosian suddenly switched to Sicilian, losing calamitously. John Saunders retraces the course of the match that decided who would defend the title against Fischer three years later.

My Chess(able) Story: Increasing my Online Rating from 1100 to

My Chess(able) Story: Increasing my Online Rating from 1100 to

World Junior Rd 3-4: Petrosian would have been proud

Happy 46th birthday to Vladimir Kramnik, the 14th World Chess

Post your World Champion Autographs Here - Chess Forums - Page 2

On Petrosian's Mysterious Style, and Difficult Opponents

EVGENY SVESHNIKOV – Cheliabimsk Warrior – European Chess Union

The petroff -_an_expert_repertoire_for_black_-_sakaev

The Caissa Kid Sharing All that is Best in Chess

Since we are talking about Tigran Petrosian once again, I decided

Botvinnik - Petrosian World Championship Match 1963 - Chessentials

World Juniors Rd.03+04: Petrosian would have been proud

Berlin Defense: Complete Guide - The Chess World

Petrosian - Spassky World Championship Match (1969) chess event

If Petrosian Sacrifices A Piece, Resign