His MLE equivalent FIP is 5.03. The dude is at best mediocre. He shouldn't be dominating a big league lineup. You can keep hiding behind K's, but when was the last time a 24 year old pitcher who was never considered a prospect before had an Almost 5 ERA and over 4 FIP in AAA, then was real good in the big leagues? It doesn't happen.
Just about any pitcher can have a good game. This dude is pitching well tonight.
