The Oakland A's will try to complete a sweep of their two-game series against the St. Louis Cardinals on Wednesday night.

Oakland right-hander Daniel Mengden (1-1, 5.09 ERA) opposes right-hander Adam Wainwright (5-6, 4.50) in the finale. Mengden begins his second stint of the season with the A's, filling the rotation spot of Frankie Montas, who was suspended 80 games for a PED violation.

Mengden, 26, pitched in five games (three starts) before being optioned to Triple-A Las Vegas on June 6. In his last major league appearance, he allowed six runs on six hits in 2 1/3 innings of relief against the Los Angeles Angels on June 5.

His last start for Oakland came on May 24, when he gave up a run on five hits in four innings during a no-decision against the Seattle Mariners. He struck out four and walked five.

After returning to Las Vegas, Mengden posted a 6.10 ERA in two Triple-A games.

"He just needs to keep his pitch count under control," A's manager Bob Melvin told the San Francisco Chronicle. "He's got the stuff to be able to pitch behind, but you don't want to have to do that. His stuff is good, but when we've seen him in the past, he's thrown a lot of pitches, even when he was pitching OK, we had to get him out a little early."

Mengden has never faced the Cardinals.

Wainwright will be making his second start since returning from a brief stint on the injured list caused by a left hamstring strain. On Thursday, he allowed three runs on six hits over 5 1/3 innings of a no-decision against the Miami Marlins. He struck out six and walked one.

He has allowed three or more runs in five of his past six outings but is 4-1 with a 2.68 ERA in seven home starts this season.

Wainwright is 2-0 with an 0.53 ERA in two career starts against the A's.

With closer Jordan Hicks slated for season-ending Tommy John surgery on Wednesday, Cardinals president of baseball operations John Mozeliak announced that Carlos Martinez would take over as the team's closer.

"Needless to say, it's very disappointing," Mozeliak told the St. Louis Dispatch regarding Hicks. "He obviously was taking over that closer role and certainly will be missed. The next question is who's going to do it, and in talking with (manager Mike Shildt), the comfort level is to go with Carlos Martinez. The good news is we have some depth there."

Martinez closed briefly last season and recorded five saves. This season, he's 1-0 with a 3.00 ERA and two saves in 13 relief appearances.

The A's started Tuesday's game without cleanup hitter Khris Davis in the lineup, as the designated hitter sat in the National League park. Davis provided a pinch-hit, two-run double in the fifth inning of Oakland's 7-3 win, and Melvin said Davis would start in left field on Wednesday.

Chad Pinder and Marcus Semien hit back-to-back homers as part of a six-run fifth inning for Oakland. Matt Olson had a homer and a single for the A's, who opened a six-game road trip with their sixth win in eight games.

Reliever J.B. Wendelken (1-1) pitched two-thirds of an inning for the win as five Oakland relievers combined to throw 5 2/3 scoreless innings with seven strikeouts.

Matt Carpenter had a two-run triple for St. Louis, and Marcell Ozuna and Paul DeJong had two hits apiece.

--Field Level Media

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