The Mariners moved out front with a pair of runs off Joe Saunders in the fifth, on two-out RBI singles by Raul Ibanez and Beltre.
Saunders allowed three runs and eight hits in seven innings. Rowland-Smith gave up three runs on four hits in 6 1-3 innings.
Seattle manager Jim Riggleman said Rowland-Smith pitched well.
"He really gave us every chance. I hated to have had to take him out when I did," Riggleman said. "Napoli had a good night. He got the sac fly and then got the big home run. He can juice the ball."
Notes
Los Angeles CF Torii Hunter missed his third consecutive game, sitting out the first two to serve a suspension for a scuffle with New York Yankees catcher Ivan Rodriguez, and this one to rest a sore quadriceps muscle. ... Beltre, playing despite needing surgery on the torn ligament in left thumb, is batting .452 (28-for-62) with 13 RBIs during his current streak.Play FOX Fantasy Football Today >
ANAHEIM, Calif. (AP) - Mike Napoli couldn't remember ever hitting a game-winning homer in the bottom of the ninth, even when he was a kid. So he really enjoyed the first one.
MLB roundup
Saturday's action
- Shields pitches Rays past Yanks
- Nady helps Yanks gain DH split
- K-Rod sets save record with 58th
- Phils gain ground on Brewers
- Braves rally vs. Santana, Mets
- Mets blank Braves in nightcap
- Twins tied for first with DH sweep
- Twins close in on Central lead
- Dodgers keep on rolling vs. Rox
- Reds' Owings haunts former team
- BoSox rally for doubleheader split
- Call-up lifts Jays over BoSox
- Bucs make it two straight vs. Cards
- Royals sweep DH from Indians
- Royals top Tribe in first of two
- A's rookie handcuffs Rangers
- Lincecum deal first complete game
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"It was a great feeling," Napoli said Friday night after his teammates mobbed him after his two-out, two-run homer gave the Los Angeles Angels a 5-3 win over Seattle. "I'd never done that before. I was just trying to get a pitch to drive to the gap."
Miguel Batista (1-7) had walked Robb Quinlan with two outs, and Chone Figgins came in to pinch-run.
"I knew if I got the ball in the gap, he could score from first because he can fly," Napoli said.
Instead, he hit a 3-1 pitch from Batista deep over the fence in left, a drive that started the crowd cheering wildly almost as soon as the ball left the bat.
