Josh Reddick drove in three runs, Scott Kazmir won for the first time in seven starts and the Oakland Athletics then waited.
The A's were so close to their third consecutive playoff appearance after a 6-2 victory at the Texas Rangers on Friday night, and would clinch an American League wild-card spot with a loss by Seattle later that night.
"Hopefully tonight we make it in there, but we're just going to keep fighting," Kazmir said, who waited with teammates in the clubhouse watching the Mariners' home game against the Los Angeles Angels. "It's not something you normally do, but it's a chance to clinch a playoff berth. We're all for it. That's for sure."
If not late Friday night, any Oakland victory or Seattle loss in the last two days of the regular season would get the A's back in the playoffs after winning the division the past two seasons.
"Go Angels," Reddick said. "I never thought I'd say that but that's what we're rooting for right now."
Adam Dunn, the big designated hitter batting in the No. 2 spot for the first time since June 2008, had a two-run double in the third for Oakland (87-73). Dunn, in his 14th major league season, was acquired by the A's on Aug. 31 and is looking to get to the playoffs for the first time.
Texas had its five-game winning streak snapped. Only their second loss in 14 games assured the Rangers (66-94) will finish last in the AL West after Houston (70-90) won at the New York Mets on Friday night.
Nick Tepesch (5-11) allowed six runs and six hits, with four walks, in 4 1-3 innings.
Kazmir (15-9) struck out five without a walk while limiting the Rangers to two runs (one earned) and four hits over seven innings.
"It's been a long time coming it feels like. Just feels good," Kazmir said.
The lefty was 0-4 with an 8.58 ERA his previous six starts since his last win Aug. 19. The 15 wins are a career high, but only four of those have come since the All-Star break.
The A's were a season-best 28 games over .500 and had a four-game lead in the AL West on Aug. 10. But they lost 29 of their next 43 games and entered the final weekend of the regular season still without a playoff spot secured.
Texas led 1-0 right away, when Leonys Martin had a leadoff single, stole second and scored on Ryan Rua's double. But Kazmir then retired 10 in a row, and the Rangers didn't score again until an unearned run in the fifth.
Martin's RBI grounder drove in Rougned Odor, who reached after first baseman Brandon Moss' error when he threw behind Kazmir, who was going to cover first base.
A's 3B Josh Donaldson landed hard on his left knee trying to make a backhanded stab of a grounder by Elvis Andrus that went foul in the third inning. After falling on his stomach and rolling over, Donaldson grabbed the back of his knee and hopped around momentarily when getting to his feet.
Donaldson sat back on the ground while being tended to by a trainer, and eventually got up and played the rest of the game. He was clearly not running full speed when he singled and eventually scored in the fifth inning.
"His knee is a little sore. We can deal with that," manager Bob Melvin said. "He was able to play in the game. We weren't going to push it."
Athletics: OF Craig Gentry, who hasn't played since sustaining a concussion in a game Sept. 9, felt good a day after watching some pitches in the bullpen and getting on the field.
Rangers: Interim manager Tim Bogar would like to get OF Jim Adduci in a game this weekend.
"Just make sure that he's mentally OK with everything before he leaves here," Bogar said. Adduci sustained a concussion Aug. 28 and is still dealing with a pinkie issue.
Athletics: RHP Jeff Samardzija, another midseason addition, is set to start the third game of the series. He is 2-2 in his past six starts despite a 1.40 ERA.
Rangers: LHP Derek Holland (2-0) makes his sixth and final start after missing the first five months of the season rehabbing from microfracture surgery on his left knee.