Alex Cobb tossed seven solid innings and the Rays won their season-high seventh in a row, 4-1, over the Mariners to open a three-game series.
B.J. Upton smacked a two-run homer to highlight a four-run third inning, as the Rays captured their sixth straight on the road and snapped Seattle's seven-game home winning streak.
Cobb (7-8) allowed one run over seven frames for a third straight start, winning all three contests. The righty scattered four hits and fanned five.
"He's gone exactly seven innings each of his last four starts between 90 and 100 pitches. You could send him back out there right there, but I'm thinking, this guy's on such a nice run doing that, why mess with it," Rays manager Joe Maddon said.
Blake Beavan (7-7) yielded eight hits and four runs over six frames, as the Mariners lost for the sixth time in eight tries. Beavan, who was 4-0 over his previous five starts, suffered his first loss since June 10 to the Dodgers.
Trayvon Robinson legged out his first career triple and scored on an Eric Thames ground single to right field in the fifth.
Prior to that, the Rays jumped on Beavan by stringing together five consecutive hits. Sam Fuld singled to right with one out and then stole second. Desmond Jennings singled on a ground ball into left field. Upton then homered tight to the line in left, an upper deck shot, for a 3-0 lead.
"(It was frustrating) not being able to make a pitch on Jennings and then getting behind on Upton and not being able to make a slider where I need to," Beavan said. "It was the right pitch, just bad location and with that guy, he just hits mistakes, and it was a mistake and he made me pay for it."
After Matt Joyce singled, Ben Zobrist laced a double to the gap in left-center for a four-run cushion.
Joel Peralta struck out the side in the eighth and Fernando Rodney worked around a leadoff single in the ninth to notch his major league-leading 37th save of the year.
Joyce has a career-high 12-game hitting streak...The Rays are 6-2 against the Mariners this season and have won 10 of the last 12 meetings...Rodney has converted 22 straight save chances, extending his club record. His 37 saves tie his career-best, set in 2009 with Detroit.