Whatever role Mike Minor ends up with in the postseason, he showed on Saturday that he could be a valuable weapon for the A’s.

Providing mixed results since joining the club just ahead of the Aug. 31 Trade Deadline, Minor closed out his regular season strong, with five innings of one-run ball in a 5-1 loss to the Mariners in eight innings in the first game of a seven-inning doubleheader at the Coliseum. The loss was Oakland’s first in extra innings this season after winning their first six in such contests, and it eliminated the A’s from contention for the No. 1 seed in the American League standings.

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After turning in a scoreless seventh, A’s closer Liam Hendriks surrendered the go-ahead run in the eighth on a single by J.P. Crawford that scored Dee Strange-Gordon, who began the inning as the automatic runner at second base, and Crawford's RBI single sparked a four-run frame for Seattle.

Minor’s numbers with the A’s are hardly spectacular -- he's posted a 5.48 ERA in five games (four starts) -- but his ability to strike batters out at a high rate could lead to a bullpen opportunity come October, a role he’s found success with over his nine seasons. The veteran southpaw limited Seattle to one run on four hits and no walks, striking out seven over five innings. In his past three starts, Minor struck out 23 while walking just five over 23 innings.

“Great again. He’s pitched really well against that team,” A’s manager Bob Melvin said of Minor. “His breaking ball seems to be getting better and better, and he maybe had his best velocity, consistently, that we’ve seen. He pitched well. We score some runs, it’s a different outcome for him.”

Averaging 91.9 mph with his heater on Saturday and maxing out at 93.7 mph, Minor constantly sat above his fastball average of 90.4 mph for the season. That velocity could go up pitching in relief with a shorter workload, and he gives the A’s training staff credit for mapping out a strength program that has helped him find the uptick in pitch speed.

“I feel a lot better now,” Minor said. “I feel like I’m making good pitches, striking guys out and limiting hits and runs. I was hoping to string a couple of quality starts together, but I do feel a lot better. My confidence level is pretty high going into the postseason.”

Melvin said “anything is possible” when asked of a potential postseason role for Minor. The lefty acknowledged a starting role is unlikely given the better numbers from other starters on the staff, and he said he’ll be fine with whatever role fits. Whenever the 32-year-old does take the mound, it will be his first postseason appearance since 2013, when he tossed 6 1/3 innings of one-run ball in a win for the Braves in the National League Division Series.

“I’m just kind of here for whatever they need me to do,” Minor said. “They haven’t talked to me about a role. I know the other guys are throwing a lot better than me, so I’m assuming they’ll get most of the work. If they need me for anything, I’ll be there.”

The A’s once again struggled with situational hitting, going 1-for-11 with runners in scoring position. Their only run came in the fourth on a go-ahead sacrifice fly by Khris Davis.