The Mariners turned to a bullpen game for the third time since Marco Gonzales hit the injured list last month, and they’re hopeful that Wednesday’s 6-3 loss in Oakland will be their last while their No. 1 starter is shelved.

• Box score

Seattle couldn’t quite put the finishing touches on what would’ve been its first sweep since last September and first in Oakland of at least three games since September 2016. But the Mariners head back to Seattle with a series win over a first-place division rival and their ace nearing his way toward being activated, manager Scott Servais said pregame.

Robert Dugger wound up giving the Mariners length, pitching into the fourth inning. But he lost his release point toward the end and was pulled after hitting Aramis Garcia to put two runners on, both of whom went on to score against Wyatt Mills. Then Mills struggled to work himself out of the jam, giving up an earned run himself on singles from Seth Brown and Ramón Laureano and a walk to Matt Chapman before getting out of it, trailing 5-0.

“His breaking balls weren't quite as tight or sharp as they have been in the past, but we knew we had to lean on him hard today based on where our bullpen was,” manager Scott Servais said. “And I thought he gave us a really good effort, just maybe not his sharpest.”

Given how James Kaprielian was pitching for Oakland, a five-run cushion proved to be plenty for the A’s to snatch the series finale and hold on to first place in the American League West. Kaprielian gave up just two hits over seven shutout innings, and though the Mariners had a mini rally going in the eighth, it proved to be too deep of a deficit to overcome.

After Wednesday, the Mariners dropped to 1-2 in these bullpen-driven contests -- but the relief corps was sharp in the first two games, including a collective outduel of reigning AL Cy Young Award winner Shane Bieber on May 16.

Thanks to three well-timed off-days in May, they avoided having to turn to the ‘pen more by reslotting their rotation in those instances. But that flexibility was fleeting, since the Mariners don’t have another off-day until June 7 and this turn through the six-man rotation will come up again on Tuesday against these A’s in Seattle.

Gonzales threw a three-inning simulated game on Wednesday at T-Mobile Park, and the reports delivered to Servais postgame were that “it went very well.” That feedback suggests that he would be in line to be activated from the IL very soon, but the Mariners will still be cautious with him even if he is 100% recovered from the left forearm strain that surfaced in his most recent start on April 27 in Houston.

Servais said that the leash on Gonzales when he returns would not be in the 85-90-pitch, five-inning range that Seattle starters are typically on. The club is going to be extremely conservative with its ace given the sensitivity of the injury and Gonzales’ previous elbow issues, even though he’s five years removed from Tommy John surgery.

“I know Marco is progressing very well,” Servais said. “I'm hopeful that this is our last bullpen day and that Marco could slide in there the next time this spot comes around. We'll just have to wait and see how that goes.”

Kelenic’s contact suggests he’s close
If it looked like Jarred Kelenic was tearing the cover off the ball over the first three games in Oakland, it’s because he was. His run-ins with defensive shifts and poor luck in general backed Servais’ suggestion that the Mariners’ new left fielder could be on the cusp of better results soon.

• Kelenic adjusting to bigs, 'learning a lot'

Kelenic went 0-for-5 on Wednesday, but he drove in a run and didn’t strike out. He also had two well-struck balls that under typical circumstances would’ve found daylight, and his popup to end the game had an expected batting average of .850 -- a reflection of the sign of his times right now.

Beyond his second career homer on Monday, seven of Kelenic’s 13 batted balls in Oakland were classified as hard-hit (anything over 95 mph), for a rate of 53.8%. The league average hard-hit rate is 39.5%, and MLB hitters have a .488 batting average on those balls. Kelenic’s batting average on balls in play was .171 entering Wednesday.

“He very easily could have had two or three hits today,” Servais said. “They make plays. That's what the big leagues are about. The defense is a heck of a lot better than [in] the Minor Leagues. But the quality of at-bats for Jarred [Kelenic is] very good. He just needs to stick there, and [hits] will eventually fall in.”