John Jaso hit a two-run homer and an RBI double for Seattle, and the Los Angeles Angels wasted a golden chance to get within one game of an AL wild-card spot with a 9-4 loss to the Mariners on Thursday.
Vernon Wells and Alberto Callaspo drove in early runs for the Angels (86-70), who had won five straight and an AL-best 16 of 23 in September before stumbling in their regular-season home finale.
Los Angeles remained stuck two games behind Oakland (88-68), which lost 9-7 at Texas, with six games to play. The Angels also fell three games back of idle Baltimore (89-67), the wild card leaders.
Hisashi Iwakuma (8-5) pitched six innings of seven-hit ball, and the Mariners avoided a series sweep by scoring six runs against the Los Angeles bullpen, which held them hitless Tuesday.
Seattle took charge in a four-run seventh inning against the Angels' inconsistent bullpen, with Garrett Richards walking in a run and giving up run-scoring drives to Kyle Seager, Jesus Montero and Jaso as Seattle went up 7-2.
Dan Haren (12-12) yielded six hits and two earned runs in 5 1-3 innings, while Howie Kendrick had a two-run double in the eighth for the Angels, who finish the regular season at AL West-leading Texas (92-64) and Seattle. Haren, who struck out three and didn't walk a batter, had won four of his last five starts, but left trailing 3-2 before his bullpen struggled.
Big-budget Los Angeles is in danger of missing the playoffs in three straight years for the first time since Mike Scioscia took over in 2000, but the majors' longest-tenured manager still has faith the Angels aren't finished.
"We're packed for as long as we have to be packed," said Scioscia, who has been told he'll return in 2013 by owner Arte Moreno. "We can recycle clothes, don't worry about it."
Torii Hunter went 1 for 5 in perhaps his final home game after five seasons with the Angels, although Moreno sounds interested in re-signing the 37-year-old outfielder.
Albert Pujols had two doubles, but struck out with two runners on to end the game in perhaps the final home at-bat of the $240 million slugger's first season in Anaheim.
Casper Wells singled and scored the go-ahead run in the fifth inning for Seattle, which will play a major role in the wild card race during the final games of its third straight losing season. The Mariners are headed to Oakland for a weekend series before returning home for three final games against the Angels.
Iwakuma picked up his fourth win in six starts, repeatedly pitching out of trouble with the Angels' surging lineup.
Haren retired the first eight batters he faced, but Jaso connected on a two-strike, two-out pitch in the fourth, popping his 10th homer into the short right-field porch to put Seattle ahead 2-1.
Kendrys Morales doubled off the right-field wall and scored on Callaspo's single later in the fourth to even it for Los Angeles.
Seattle went back ahead when Wells scored on a grounder by Franklin Gutierrez, who narrowly avoided an inning-ending double play by beating an off-target throw. Gutierrez then was thrown out at the plate by relay man Howie Kendrick after Seager's double off the wall.
Michael Saunders' single off Nick Maronde started the seventh-inning rally by the Mariners, and Trayvon Robinson drew a bases-loaded walk from Richards with one out. After Seager's single and Montero's sacrifice fly, Jaso chased Richards with a double.
NOTES: Angels LHP Andrew Taylor, a 34th-round draft pick in 2008, made his major league debut in the ninth. ... Angels C Chris Iannetta left the game in the eighth inning with leg cramps. ... Angels SS Erick Aybar stole his 20th base in the second inning, giving him 20 steals for the third straight season. ... Gutierrez made a spectacular running catch at the wall in center field in the fifth inning, robbing Mike Trout. Gutierrez was shaken up by his collision with the wall, and he left the game an inning later. ... The Angels drew 3,061,680 fans to the Big A this season, surpassing 3 million for the 10th consecutive season since their only World Series title.