Hisashi Iwakuma tossed seven innings of one-run ball to lead the Mariners to a 3-2 win over the Astros at Safeco Field on Monday.
The right-hander allowed just an unearned run and lowered his ERA to 1.79 on the season. Iwakuma gave up just four hits, one walk and struck out eight.
Carter Capps and Charlie Furbush combined to throw a scoreless eighth and Tom Wilhelmsen worked around a run in the ninth to lock down his 16th save of the season.
Down 1-0 in the fourth, Raul Ibanez tied the game with his 12th home run on the year.