Since joining the club in 2016, the A’s grew accustomed to having Khris Davis as the club’s main run-producer as he established himself as one of the game’s elite power hitters. So when Davis’ struggles this season relegated him to a bench role, that development hit his teammates perhaps even harder than it did him.

That’s why when Davis smacked a fastball from Zack Greinke over the right-field wall in the third inning of Tuesday’s 4-2 win over the Astros in the first game of a seven-inning doubleheader at the Coliseum, the A’s dugout erupted with a standing ovation as he rounded the bases. KD finally looked like KD again.

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“We’re trying to find the right matchups to get him going again,” A’s manager Bob Melvin said. “With the injuries and so forth, this is the type of guy that can carry a team. Every game he doesn’t play hurts me some. To his credit, he’s working really hard and feels good about where his swing is right now.”

In the starting lineup for the first time since Aug. 26, Davis’ shot off Greinke, which gave the A’s an early 1-0 lead, was just his second homer of the year and first since Aug. 3. The blast was part of a 2-for-3 day that also saw him drive in an important insurance run on a booming RBI double that extended the lead to 4-2 in the sixth.

Davis’ history against Greinke played a part in him getting the start -- he entered the day 3-for-8 with a home run and double against the right-hander. But Melvin also noted that Davis has been putting in a lot of work with hitting coaches Darren Bush and Eric Martins over the past two weeks.

“It was big. He’s really done some good work and felt good about himself,” Melvin said. “Guys show up at different times when they need to, and he certainly showed up for us today. You want to credit a guy who worked really hard and has had to take a demotion. That is hard to do based on what he’s done for us the previous three years.”

A good sign in past years that would let Melvin know Davis was swinging well was when he was hitting the ball to the opposite field. Both the homer and double on Tuesday were hit to right field, and both were hit hard, registering 104.2 mph or harder off the bat, according to Statcast.

“That’s what he does. That’s his game, and that has kind of left him a little bit,” Melvin said. “You get a little antsy and want to try to pull the ball. It was good that he stayed with it. That’s been his sweet spot over the years. You saw the way the dugout reacted. Everybody pulls really hard for Khris.”

Davis’ breakout helped Frankie Montas bounce back from some struggles of his own.

Coming off an ugly stretch that saw him post a 16.76 ERA over his past three starts, Montas got things back on track. The right-hander limited the Astros to two runs on six hits as he struck out four batters over five innings. His only mistake came in the fifth on a two-run homer surrendered to Michael Brantley that just scraped over the right-field wall.

With Tuesday’s win in Game 1 of the doubleheader, the A’s extended their lead atop the American League West to 5 1/2 games over second-place Houston. Is the pressure starting to mount for the Astros?

“I don’t think any of us are thinking about the pressure the Astros have. That’s their job, to think about if they have pressure or not,” Montas said. “We’re chilling over here. Just trying to play good baseball.”