Moore was hit in the head for the second time in a week, taking a 92 mph fastball from Houston Astros reliever Brandon Bielak off the helmet in a 6-1 win over Houston on Monday night. Moore remained in the game but began to feel effects afterward, Mariners manager Scott Servais said.
Moore also briefly stayed in the game after taking a 99 mph pitch to the head from San Francisco Giants reliever Sam Coonrod last Wednesday. He was pulled before taking the field the next inning. Moore returned to the lineup the next day.