Veteran pitchers who were slotted back-to-back in the Kansas City rotation earlier this season go head-to-head for the first time in their career when the Royals and host Oakland Athletics conclude a three-game series on Wednesday afternoon.

The tightly contested set has produced a pair of come-from-behind, one-run wins, the result being that the A's (91-61) own a two-game lead over Tampa Bay (89-63) and a 2 1/2-game advantage over Cleveland (88-63) in the race for two American League wild-card playoff berths.

Coming off a 2-1 win on Tuesday night, the A's will send right-hander Homer Bailey (13-8, 4.76 ERA) in pursuit of his career-best 14th win in the series finale.

Bailey started the season with the Royals, where he joined left-hander Danny Duffy (6-6, 4.55) in the starting staff during the first half of the year.

That changed when the A's acquired Bailey in mid-July, a deal that's worked out well for Oakland. Bailey has gone 6-2 with a 4.70 ERA in 11 starts with his new team.

Bailey made a successful return to Kansas City last month, riding massive offensive support to a 19-4 win. He served up a home run to Brett Phillips during his six-inning stint.

It was the 33-year-old's only career start against the Royals, against whom he will take a 1-0 record and 4.50 ERA into Wednesday's duel.

Marcus Semien did much of the damage for the A's that night, driving in seven runs with a three-run homer, a three-run triple and an RBI infield out.

"(The coaches) talk about it every day: He's been fantastic," A's manager Bob Melvin said about Semien earlier in the series. "Durable, power, average, on-base, defense ... he's one of the better players in the league."

Semien has one career homer in 11 at-bats against Duffy, who has dominated the A's over the years, going 4-0 with a 2.89 ERA in eight games (seven starts).

All of the wins have come in six outings (five starts) in Oakland.

Duffy, 30, missed the A's on their visit last month. He has since pitched well in his past two starts against Miami and Houston, allowing just two runs and six hits in 12 innings.

He benefitted in the 7-2 win over the Marlins from Jorge Soler's 41st home run of the season.

Soler has belted nine homers in his past 18 games, including one Monday in the Royals' 6-5 win, to catch injured Los Angeles Angels star Mike Trout for the AL with 45.

Soler told reporters Tuesday that he's not dwelling on winning a home run title.

"All I want to do is stay focused and swing at good pitches," he said. "I'm not worried about that other stuff. I'm not going to worry about who's leading or not leading. All I want to do is to keep doing what I'm doing."

On Wednesday, Soler has a chance to equal former A's outfielder Jose Canseco's 1998 feat of 46 homers, the second-highest single-season total ever produced by a Cuban-born player. Rafael Palmeiro passed Canseco and set the record with 47 in 1999, then duplicated the total in 2001.

--Field Level Media