When a rookie pitcher gets a September call-up, one of three things generally happens:
- They look bad;
- They look mediocre; or
- They look good!
Adam Wainwright of the Cardinals came up in September and put up a 13.50 ERA, but followed that up with a 3.12 ERA the next year. There are many other instances of where pitchers did not impress in their September auditions, but came back and were excellent.
Walker Buehler was a September call-up and if you look at his overall stats, you may not be impressed: 9.