Morrow allowed one run and five hits in his first spring appearance since March 14. He missed his start on March 19 after experiencing right shoulder soreness while warming up, and threw in a simulated game on Monday.
Morrow, expected to be Toronto's fourth starter, went 2-4 with six saves in 26 appearances for Seattle last year.
Houston starter Bud Norris allowed seven hits and seven runs in 2 1-3 innings. Norris, who is fourth in Houston's rotation, walked two and struck out three.
Edwin Encarnacion homered and drove in four runs for Toronto.