ST. PETERSBURG -- Rays center fielder Kevin Kiermaier needed only half of Wednesday’s doubleheader to have a career day at the plate. Actually, he needed only two at-bats.

Kiermaier knocked a two-run double to right field in the first inning of the Rays’ 8-1 Game 1 victory over the Indians on Wednesday afternoon at Tropicana Field. He then blasted a three-run homer to right in the third inning off right-hander J.C. Mejia. Just like that, three innings into a straight doubleheader, Kiermaier had recorded a career-best five RBIs and put the Rays on their way to their third straight win.

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“As he was yelling afterward, he's a second-half player,” Rays manager Kevin Cash said with a grin. “So I hope he's right.”

Kiermaier has been hitting better of late, going 9-for-29 in his last nine games. His best performance of the season came in the Rays’ 86th game. So … maybe he’s on to something?

“Trying to have a good sense of humor about just kind of how the season has gone for me personally, but I'm heading in the right direction, getting great work in, and I'm just trying to be the best player I can be from this point right now moving forward,” Kiermaier said. “I'd much rather make the adjustment sooner than later, but this is what happens throughout the course of a season. But I'm starting to feel a lot more locked in, and hopefully I can just find that consistency along the way.”

Right-hander Michael Wacha gave the Rays an excellent start, allowing only four hits with six strikeouts and no walks in six innings. Brandon Lowe continued his recent tear, crushing his 18th home run of the season. And No. 2 prospect Vidal Bruján made an immediate impact with his first career hit, RBI, stolen base and run while also making a nice play at second base in the first inning of his big league debut.

But it was Kiermaier, Tampa Bay’s longest-tenured veteran, who made the biggest impact in the first of two seven-inning games against Cleveland. While he’s still playing his excellent brand of center-field defense and providing important leadership in the clubhouse, Kiermaier has been relatively quiet at the plate in the first half. He entered Wednesday hitting just .232 with a .595 OPS and one home run in 199 plate appearances.

That changed in a hurry. Bruján got the scoring started in the first inning against Mejia, smacking a 107-mph single to right field to score Joey Wendle from second base, then stole second to put a pair of runners in scoring position. Up came Kiermaier, who swatted a 2-2 changeup to right to give the Rays a 3-0 lead.

“He works hard on staying through the middle or maybe at times the other way, but watching him get some balls that he could drive and pull into the gap or down the line, it is a good sign,” Cash said. “KK's got some power when he's at the plate.”

The Rays rallied again in the third, as Wendle doubled and Austin Meadows walked before Kiermaier came to the plate with two outs. He worked a full count, then unloaded on a high full-count fastball from Mejia, ripping it into the right-field seats. It was Kiermaier’s first game with multiple extra-base hits since he doubled twice in Game 1 of last year’s American League Championship Series against the Astros, and he knew it was the first time he’d driven in five runs.

“Rounding the bases, I was like, ‘OK, this is a first time for me,’” Kiermaier said. “Anything you can do to help the team win and create momentum for you and the boys out there, that's what it's all about.”

Lowe tacked on a run against reliever DJ Johnson, crushing a 110.2-mph solo shot to right field in the fourth inning. Lowe, who has been working on his swing after an admittedly disappointing and frustrating start, has now gone deep in back-to-back games, four times in his last six games and six times in his last 13. Brett Phillips also homered in the sixth, rounding out a game in which all eight Rays runs scored with two outs and two strikes.

That was plenty of run support for Wacha, who bounced back from a rough bulk-inning relief outing a week ago with one of his best starts of the season. The veteran righty returned to the role and routine of a starting pitcher and allowed only a solo homer to Franmil Reyes while working his way out of two jams in a season-high-tying six innings. Wacha’s changeup was particularly baffling for Cleveland’s hitters, who swung 18 times at changeups and whiffed on 12 of those swings.

“The way that we were using it today, I think it was just keeping them off-balance. I was putting them in a good spot to get some weak contact and swing and misses,” Wacha said. “Not too many of them were down the middle and elevated. That pitch is always pretty much a lot [more] effective whenever it's down in the zone in a much better spot for me."