OAKLAND -- The A’s bullpen has taken its lumps this year, responsible for losing several games that appeared to be in hand. To make matters worse, it was down two of its top relievers on Friday. But on this night, it was that same maligned bullpen that shined.

At the forefront of an impressive showing by A’s relievers was Lou Trivino, whose three scoreless frames in extras kept the game tied long enough for Robbie Grossman's walk-off single off Astros reliever Cy Sneed in a 3-2 victory in 13 innings at the Coliseum.

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The win brought Oakland within 7 1/2 games of Houston for first place in the American League West and a half-game back of the Rays for the second AL Wild Card spot.

Following two hitless innings by Joakim Soria, Trivino took the ball to begin the 11th and struck out Carlos Correa on three pitches, finishing him off with a blazing 98 mph fastball. That began his near-flawless outing in which he allowed only a hit and a walk as he racked up four strikeouts.

“That’s huge for him,” A’s manager Bob Melvin said of Trivino. “You have to go out there and be perfect. If you’re not, you lose the game. I think it was big for his confidence as well. That’s a really tough lineup that he went through. Three innings, he hasn’t done that in quite some time, so that was really impressive to see.”

Expected to shore up the back end of the bullpen in 2019 after a meteoric rise to the setup role in his standout rookie campaign last season, Trivino has been mired in a sophomore slump. The right-hander entered Friday with a 5.14 ERA, but he and three other A’s relievers combined to keep the Astros off the board for seven innings in relief of starter Tanner Roark, who tossed six frames of two-run ball.

The A’s were down closer Liam Hendriks and Yusmeiro Petit, as Melvin wanted to give both a day off after heavy workloads the past few days. With eight days going by since his last outing, Trivino knew if there was any reliever who would be called upon to go multiple innings, it was going to be him.

Trivino hadn't pitched since Aug. 7, when he recorded only one out and gave up a two-run homer in a loss to the Cubs. After that game, Melvin suggested Trivino needed to have “more faith” in his fastball in order to turn things around. The right-hander listened to that advice, as 30 of his 41 pitches against the Astros went for strikes.

“Sometimes, I get too cutter-happy, and this year, my cutter has been inconsistent,” Trivino said. “When I back it up, it’s a little easier to hit. But at the same time, it’s throwing it when it’s unexpected. I know the book on me is I’ll throw a cutter anytime, but today, I threw the curveball a little more.”

It was the cutter that led to Trivino's 2.92 ERA over 74 innings last year, but if he is going to regain success in 2019, he said it will have to come by throwing all four of his pitches for strikes, like he did Friday.

“These hitters are so good, you can’t sit there and throw one pitch unless you’re Mariano Rivera,” Trivino said. “Unless you have that special pitch. Last year, I thought my cutter was phenomenal, but this year, it’s just not the same, consistency-wise. Once in a while, it’ll back up, where it didn’t really last year. You can’t expect to not get hit unless you have a Josh Hader or Craig Kimbrel fastball. If I can throw four pitches at them, why not?”

If Trivino’s three-inning magic seemed familiar, it’s because he’s done it before. The last time he pitched three frames came at Yankee Stadium last October in the AL Wild Card Game, when he held the Yankees scoreless. The A’s lost that game, but they saw Trivino gain the confidence of a rookie who truly knew he belonged.

Somewhere along the way in 2019, that confidence was lost. But if they’re going to catch the Astros or Rays to make the postseason, they know they’ll need Trivino at his best.

“I hope he can carry this momentum for the rest of the season,” A’s third baseman Matt Chapman said. “Everything that has already happened doesn’t matter. It’s all about how we finish. We’re in the playoff hunt, and to have him pitch like that is huge. I think he should just build off this and try to finish strong. Put the numbers away and help the team win.”

Roark duels Verlander

Though they went about it in different ways, A’s starter Tanner Roark and Astros starter Justin Verlander dueled during a scoreless stalemate through four innings. Verlander was flashier, racking up seven strikeouts in three innings, while Roark pitched around traffic and battled to keep the Astros off the board.

Verlander outlasted Roark by one inning, but by the time they were finished, both starters left with the game tied at 2.

“I kind of think of it that way, me facing the opposing pitcher,” Roark said. “I try to outlast or keep up with the other starting pitcher and try to be better. He goes out and puts up zeros, I want to do the exact same thing.”

“Going against Verlander, he knew he had to be on it and get off to a good start,” Melvin said. “All the way across the board, to get that kind of pitching effort, everybody had to contribute.”

Roark completed six innings for the second consecutive start, marking the first time he’s gone back-to-back outings of at least six since June 15 and June 20.

The A’s offense provided Roark support with a pair of solo home runs by Mark Canha and Marcus Semien, who both took Verlander deep. Canha’s homer was his 18th, setting a new career high, while Semien reached the 20-homer mark for the second time in seven big league seasons.

Though Roark was long out of the game by the time Grossman walked it off, the adrenaline of yet another tight game against the Astros kept him energized throughout the night.

“I’m still sweating,” Roark said. “We battled all night long facing one of the greatest. We had runners on and they did a good job of shutting us down. But we finally broke through.”