Add one more to the list of 'Greatest Players Never To Have Won The World Chess Championship' - Viktor Korchnoi, born in 1931, was defeated by Anatoly Karpov in 1974 in the match to decide who would take Bobby Fischer's vacated world title, and though he won the right to two further rematches, never seriously looked like being able to beat Karpov.
Korchnoi's style is famously uncompromising and attacking, and, unusually for a chess player, he has maintained this dynamic approach to the game despite now approaching his seventies, a time when most still-active Grandmasters prefer to play positionally, drawing on their vast experience to defeat hot-headed younger opponents. His personality matches his chess, and he was banned from tournament play for six months after criticising Karpov's tactics in their first world championship match. For this and other reasons, he defected from the then Soviet Union and became a Swiss national in 1976.
His matches with Karpov were noteworthy for the weird behaviour of both players, which did a lot to contribute to the public perception of top chess players as bordering on the insane. A wooden panel had to be installed underneath the table to stop the players from kicking each other's shins, and Korchnoi began to wear large mirrored sunglasses because he claimed that one of Karpov's supporters in the front row was trying to hypnotize him. Korchnoi could also be found in his room at odd times of the day chanting mantras while performing a headstand, together with members of a minor cult with whom he had some affiliation. However, it would be unfair to contribute further to the sensationalization of these kind of stories, as Korchnoi is also a highly articulate and sensitive man, who once described his relationship with his estranged wife as "Like bishops of opposite colours."