When Karpov 's team sent him a bilberry yogurt during a game without any request for one by Karpov , the Korchnoi team protested , claiming it could be some kind of code ( such as whether Korchnoi was dead equal or slightly advantageous ) .
When Karpov 's team sent him a blueberry yogurt during a game without any request for one by Karpov , the Korchnoi team protested , claiming it could be some kind of code .