SEATTLE -- Marcus Semien's two-run homer in the 13th inning lifted the A's to a 7-5 victory over the Mariners on Saturday night at Safeco Field.
Danny Valencia spotted Oakland a 3-0 lead in the first with his 18th home run of the season and Brett Lawrie's sacrifice fly in the ninth tied the game at 5 before Semien hit the game-winner off reliever JC Ramirez. Robinson Cano cracked a three-run homer in the third and Ketel Marte's RBI single in the sixth gave the Mariners a 5-4 lead, but they lost for the ninth time in their past 10 games.
"A guy that perseveres through a lot, doesn't let the negative things get him down and then ends up getting the huge home run for us," A's manager Bob Melvin said of Semien, who made his 34th error of the season in the fifth, a new Oakland record. "Tonight was huge and just kind of tells you about the character he has."
Seattle starter Roenis Elias lasted just two-plus innings, allowing four runs on seven hits before giving way with the bases loaded and no outs in the third. He closed out his second season at 5-8 with a 4.14 ERA. Sean Nolin, making his sixth start for the A's since being acquired in the Josh Donaldson deal, gave up three runs on six hits over five innings to finish his rookie season at 1-2 with a 5.28 ERA.
MOMENTS THAT MATTERED Switcheroo: Switch-pitcher Pat Venditte, who allowed eight runs in 12 September appearances, celebrated the new month with three perfect innings in relief, keeping the Mariners off the board in the 10th, 11th and 12th innings while the A's staged a rally for the win. Felix Doubront notched a save with a 1-2-3 13th inning.
"He's had spurts where he's pitched really well for us," Melvin said of Venditte. "A couple of bad outings and some really good ones and no more than this one."
Cano still a-go: Cano is scheduled for postseason surgery on a sports hernia that has hampered him the past two months, but the Mariners second baseman is closing out strong. Cano rallied the Mariners from a 4-0 deficit with a three-run blast in the third off Nolin, giving him 21 homers and 79 RBIs on the season. Cano extended his hitting streak to 15 games -- longest current streak in the Majors -- with a 2-for-5 night that raised his season average to .287.
"Robbie has been swinging it great," said Mariners skipper Lloyd McClendon. "He continues to battle. He gave us a big hit tonight and got us back in it. We had the lead in the ninth inning and had a chance to win it."
Homer happy: Valencia, who was a triple short of the cycle in Friday's series opener, picked up right where he left off and smashed a three-run homer to center field in his first at-bat Saturday, singling and scoring in his next one. The third baseman has totaled 11 home runs and 37 RBIs in 46 games since joining Oakland off waivers from the Blue Jays on Aug. 5.
Zych stems the tide: Rookie right-hander Tony Zych continued his impressive work as a September callup for the Mariners with three scoreless innings of relief, with one hit and four strikeouts. Zych entered a bases-loaded jam left by Elias with no out in the third and minimized that problem with three straight groundball outs -- on six pitches -- by Stephen Vogt, Semien and Craig Gentry. Vogt's fielder's choice scored one run to make it 4-0, Zych's quick work kept Seattle within striking distance and they eventually took a 5-4 lead in the sixth. More >
"He had nothing." -- McClendon on Elias' short start
WHAT'S NEXT A's: The A's will close out their season Sunday with right-hander Chris Bassitt on the mound for a 12:10 p.m. PT start against the Mariners at Safeco Field. Bassitt is 0-2 with a 5.56 ERA in three appearances (two starts) against Seattle this season.
Mariners:Vidal Nuno (1-4, 4.19) starts Sunday's season finale for the Mariners. The 28-year-old swingman is 0-1 with a 10.00 ERA in nine innings against the A's in five career meetings, including two starts.
Greg Johns is a reporter for MLB.com. Read his Mariners Musings blog, and listen to his podcast.
Jane Lee is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.