Castillo is making his ninth start as an opener for the Rays. The rookie right-hander has a 2.92 ERA and opponents are hitting .200 off him in his eight starts although he has yet to pitch more than two innings. The Rays are 7-1 in those eight games.
Mendez has made two starts and one relief appearance since being called up for September, and he is 2-0 with a 1.20 ERA this month. In 15 innings, he has allowed seven hits and seven walks while striking out 10.