Tough choice, indeed. However, I'm giving the ball to Catfish Hunter. During his prime, i.e. the 72-74 World Series, he was 4-0, with an ERA under 1.75.
With Catfish, it was never about stats, though. He almost always found a way to give up one fewer run than his teammates gave him. That's what made him such a money pitcher.
Not denigrating Gibby or Koufax, either. I saw both of them pitch at Candlestick Park against the Giants.
Gibbys World Series career ERA was 1.89.
Koufax pitched must-win pennant clinching games twice I think 65 and 66. I believe his career record in 1-0 games was 11-3!
Having grown up in the golden era of the 60s and 70s, I never saw a money pitcher quite as reliable as Koufax.he seemed to get better the more important the stakes.
Walter Johnson.