McCullers threw a scoreless inning, striking out one batter, in Wednesday's 3-1 loss to the Blue Jays.
McCullers, who was activated from the disabled list earlier this week, made his first appearance since Aug. 4, when he left a start against the Dodgers with a strained right forearm muscle. He needed just 11 pitches to navigate the second, third and fourth hitters in Toronto's lineup. He threw his signature curveball five times, eliciting two swinging strikes, and another called strike. The right-hander will pitch one more time this weekend against Baltimore, after which the organization will evaluate McCullers for a spot on the postseason roster.