In 1999, 36-yr-old Chuck Finley became the only pitcher to strike out 4 batters in an inning twice in a career. He did it in the twilight of his career, and within a single year. Oh and he also did it AGAIN during that time.

Chuck Finley was a stellar pitcher 1986-1998, with a 3.66 ERA and 4x AS. He had a 4.45 ERA thereafter. In May 1999, at age 36, he struck out 4 batters in an inning for the first time. Then, in August, he did it again, making him the first pitcher to have multiple 4-strikeout innings... then he did it AGAIN April 16, 2000. He is the only guy to have 4K's in an IP thrice in a career, and he did it in the twilight of his career, and within a single year.