With a pitching staff decimated by injuries, the Athletics will be leaning heavily on the right-hander to help anchor the rotation.
Fiers remained unbeaten in an Oakland uniform, working six solid innings to lead the Athletics past the Baltimore Orioles 3-2 on a damp Tuesday night.
"I feel like if I do my job, I'm going to get a win," Fiers said. "Keeping a team within a couple runs with the way our team is and the way we swing the bats, I find myself in a good chance to win us the game."
Oakland extended its winning streak to five games and is 33-15 since the All-Star break, the best mark in the majors during that span. The Athletics hold the second AL wild-card spot behind the Yankees.
Fiers (12-6), who was acquired from the Tigers on Aug. 6, allowed one run and four hits with seven strikeouts and a walk. He is 5-0 in seven starts with the A's and has won a career-best six straight decisions overall.
"It seems like other than one (start), maybe, that's pretty much what he's been giving us," Oakland manager Bob Melvin said. "Six innings and a lead when he leaves. Seems to get a little stronger at times as the game goes along."
Stephen Piscotty went 3 for 4, including an RBI single in a three-run third inning. He extended his hitting streak to 12 games and has driven in a run in six straight.
"It just seems like every time we need somebody up in a big situation, (Piscotty) comes up and either hits a home run or gets a big hit to extend the lead or whatever it will be," Melvin said.
Adam Jones was back in the starting lineup for the first time since last Wednesday and had a pair of hits for Baltimore, which has lost five straight and has the majors' worst record (41-103). Jonathan Villar drove in both Orioles runs with a homer off Fiers in the sixth and a single in the eighth off Lou Trivino.
Jeurys Familia, acquired from the Mets on July 21, worked a perfect ninth for his 18th save overall.
Orioles right-hander Alex Cobb, who was scratched from his scheduled start Sunday with a blister on his throwing hand, pitched two scoreless innings before departing with the same injury.
"I thought he was on his way to another good outing tonight and he was crisp, carrying a good fastball," manager Buck Showalter said. "He was really frustrated up the runway, regardless of what kind of stuff he might have been carrying and what he could have done."
Mike Wright (3-2) entered in the third and was hit in the left foot by a sharp grounder from Ramon Laureano, the second batter he faced. Matt Chapman followed with an RBI double, and Khris Davis and Piscotty drove in runs with singles.
Wright settled down to retire the next seven batters.
WINNING LATE, WINNING CLOSE
The A's are the only team in baseball that has not lost when leading after seven innings, going 64-0. Oakland is also 28-12 in one-run games, the second-best mark in the majors behind Seattle.
Athletics: RHP Frankie Montas was recalled from Triple-A Nashville. Montas has started 11 games for the A's this season, going 5-4 with a 3.96 ERA.
Orioles: OF DJ Stewart had his contract selected from Triple-A Norfolk. His first appearance with the Orioles will be his major league debut. ... RHP Cody Carroll was recalled from Norfolk. He has allowed seven runs and eight hits with nine walks over nine innings with Baltimore this season. ... C Andrew Susac was reinstated from the restricted list.
Athletics: LHP Sean Manaea will have season-ending surgery on his left shoulder next week in Los Angeles. Manaea has been on the disabled list since Aug. 26. The 26-year-old Manaea went 12-9 with a 3.59 ERA and 108 strikeouts in 160 2/3 innings this year.
Orioles: OF Mark Trumbo (right knee surgery) and RHP Pedro Araujo (right elbow sprain) were each transferred to the 60-day disabled list.
Athletics: Liam Hendriks (0-1, 6.32 ERA) is slated to make his third start of the season. He is expected to work an inning or two.
Orioles: Andrew Cashner (4-14, 4.89 ERA) is looking to stop a four-game losing streak. In his last outing, Cashner allowed three solo home runs in a 5-3 loss to the Mariners.
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