Riddle: Korchnoi-Karpov 1978 (opens in new tab)

As chess players occasionally do, Alex Fishbein, the U.S. grandmaster, was recently looking at a classic game from the past: Viktor Kortschnoj's victory over Anatoly Karpov in the 21st game of their 1978 match. Something was wrong. Charles Sullivan had done some intense research on this volatile encounter and asks for your assessment on the results he presents.