Seattle - Hisashi Iwakuma struck out a career-high 13 and Michael Saunders and Kyle Seager had two hits apiece to help Seattle win its fifth consecutive game 4-1 over the Toronto Blue Jays.
Iwakuma (2-2) struck out Rajai Davis three straight times after allowing Davis' first career leadoff homer, which gave the Blue Jays a brief 1-0 lead.
Iwakuma's 13 strikeouts broke the Mariners rookie record of 12 previously shared by Mark Langston, Randy Johnson and Freddy Garcia. Iwakuma threw eight innings, allowed four hits and walked three.
Toronto starter Ricky Romero (8-8) went six innings, allowed eight hits and three earned runs. He struck out seven and walked two. Romero has lost seven consecutive starts.