Korchnoi's record vs. Fischer is +2 =4 -2, so there's not much reason to think that Karpov beating him narrowly (until Merano '81, when he won convincingly) tells us much about his chances against Fischer.
Anyhow, Tolya's holding his own so far. Here's game three:
Joshka: Many folks try to claim a Karpov victory over Bobby in 1975, cause Karpov beat Spassky in their finals match. Well Fischer demolished Spassky in their match in 1972. Take away the forfeit win for Spassky, a game never played, and Spassky won 2 games!!!.....and one of those 2 wins, was Bobby's Bishop takes h2 experiment. So all in all Boris beat Bobby one time in the match. Korchnoi, 20 years Karpov's elder, gave Karpov everything he could handle in the 1974 finals match, and nearly beat Karpov in their 1978 match! Bobby would have won hands down in 1975, 1978, and probably 1981.