With a chance to advance Tuesday, the bullpen couldn't come through.
Sean Doolittle lost the lead and gave up two runs in the seventh inning, Ryan Cook and Brett Anderson yielded three more in the eighth, and the Tigers rallied for an 8-6 win to force a decisive fifth game in their AL division series.
"It's really frustrating, but I wouldn't have done anything different," Doolittle said. "I just got beat."
A's manager Bob Melvin, likewise, wouldn't second-guess his decision to take out rookie Dan Straily after he gave up three runs over six innings. Melvin gave Doolittle the ball with a 4-3 lead in the seventh.
"When Daniel came out, we had one of our best relievers in the game," Melvin said.
Entering the game, Oakland's relievers had held Detroit scoreless for eight innings and hadn't allowed a run in the previous nine games dating to the regular season.
That's why Melvin wasn't willing to be too hard on his relievers for letting a big win slip away.
"We put a lot of faith in our bullpen," he said. "One of the reasons that we are where we are is because of our bullpen."
But now, the Tigers are heading back to California thanks to Max Scherzer and perhaps some fans in the stands.
During a relief outing to remember, Scherzer escaped a major jam one inning after two fans reached out to try to reel in Victor Martinez's disputed home run that helped the Tigers extend the series.
Playing from behind most of the way, Detroit tied it first with Jhonny Peralta's three-run homer in the fifth and then on Martinez's solo shot in the seventh. A couple of fans attempted to catch Martinez's drive, and at least one of them bobbled the ball as he reached over the railing above the wall, preventing right fielder Josh Reddick from having any chance at a leaping grab.
Umpires upheld the home run after a replay review.
"It was clear he was not going to catch the ball, so it was clearly going to be a home run," said Gary Darling, the crew chief and right-field umpire. "There wasn't any other evidence on replay to turn it another way."
Reddick and center fielder Coco Crisp immediately protested, pointing up at the stands in the hope of a fan-interference call. After the game, Reddick said he thought the homer should have been negated by fan interference because there was no doubt in his mind he was going to catch the ball.
"It changed the momentum for them, it changed the momentum for us," he said. "It's totally frustrating that a fan can influence the game."
Scherzer, making his first relief appearance since the 2011 postseason, gave up a run in the seventh and got in trouble again in the eighth. With the Tigers up 5-4, he allowed a walk and a double to start the inning. After an intentional walk to load the bases with none out, manager Jim Leyland left his 21-game winner on the mound.
Scherzer struck out Reddick and Stephen Vogt before getting pinch-hitter Alberto Callaspo to line out to center.
Detroit, hitless through the first four innings against Straily, added three runs in the eighth on a wild pitch and a two-run double by Omar Infante that made it 8-4.
Yoenis Cespedes hit a two-run single in the ninth, bringing the potential tying run to the plate, but Joaquin Benoit struck out Seth Smith to end it.
The Tigers will now send Justin Verlander to the mound for Game 5 on Thursday night in Oakland. Verlander shut out the A's at the Coliseum in the decisive fifth game of the division series last year.
Oakland hasn't announced a starter for Game 5. It is Bartolo Colon's turn in the rotation, but rookie Sonny Gray could also come back on normal rest after a brilliant performance in Game 2.
Crisp had four hits and three runs for the A's, who led 3-0 and 4-3 but couldn't close out the defending American League champions.