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.

The Petrosian Variation in the French Defense (Or Is It?)

The Tactical Side of Petrosian You Didn't Know About!

Quality Chess Blog » Looking into 2018

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

The petroff -_an_expert_repertoire_for_black_-_sakaev

Taking Risks in Chess: My Experience Against a Master — Eightify

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

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

Viktor Korchnoi Armchair Warrior

Middlegame Archives - British Chess News

Tigran Petrosyan's response to Wesley So's accusations. : r/chess

The petroff -_an_expert_repertoire_for_black_-_sakaev

The Caissa Kid Sharing All that is Best in Chess

Tournaments Archives – GM Alex Colovic