SEATTLE -- The A’s remain unable to find a cure for their woes against the Mariners this season. Due to those struggles, they’re now on the brink of elimination from playoff contention.

A season-long saga of frustrations against the Mariners continued on Monday in a 13-4 blowout loss at T-Mobile Park. Now having dropped five games against Seattle over the past eight days, Oakland’s quest for a fourth straight postseason appearance is nearly vanquished at 3 1/2 games back of the second American League Wild Card spot with five games left in the regular season and two teams in front of them.

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A poor record against the AL West as a whole has contributed largely to the A’s finding themselves in this unfavorable position. No team may be more responsible for derailing their playoff hopes than the Mariners. Now 4-13 in head-to-head matchups this season, Oakland has lost 10 straight against Seattle, matching its longest losing streak against any team since dropping 10 in a row to Houston from July 20, 2016-April 28, 2017.

“They’ve had their way with us,” said A’s manager Bob Melvin. “But when we take the field tomorrow, we expect to win. It doesn’t feel very good to get beat that many times by one team. But you have to go out there and earn it the next day.”

The A’s carried over the good vibes from a weekend three-game sweep of the Astros into Seattle early. After back-to-back two-out singles by Matt Olson and Mark Canha in the first, Seth Brown delivered with a three-run home run off Mariners starter Chris Flexen.

It was an early three-run lead that Cole Irvin was unable to hold onto, as his personal struggles against the Mariners also continued. Pulled after issuing two consecutive walks to begin the fourth inning, Irvin allowed five runs on six hits and three walks.

Though Irvin has emerged from a Spring Training longshot into a surprisingly strong contributor, the Mariners have continuously hit him hard throughout the year. In five starts against Seattle, Irvin became the first pitcher in Major League history to go 0-5 in a season against the Mariners, with his 8.69 ERA (19 earned runs in 19 2/3 innings) also the highest of any starter with a minimum of five starts against Seattle.

"They're in the playoff race for a reason. They're a good club,” Irvin said. “They find ways to win ballgames, and they have a lot of success against us. On my end, I haven't pitched well.”

Following Irvin’s first start against the Mariners this season on May 25, an outing in which he allowed four runs on 10 hits and lasted just 4 2/3 innings, the left-hander made some comments in a postgame Zoom session that could have been perceived as a slight. Asked about his performance that day, Irvin said he was displeased with his pitch execution and said, “a team like that should not be putting up 10 runs against me or anyone” in reference to Seattle’s offense.

Fast forward to four months later. Irvin went through the season never going past the fifth inning in any of his five starts against the Mariners. After Monday’s loss, Irvin said that while he meant no disrespect by those comments he made back in May, he could see how that could be something Seattle continues to use as bulletin-board material.

“Baseball has a way of humbling itself,” Irvin said. “To be honest, it goes back to the comments I made early in the season. They’re hungry every time. They want to face me and beat me into the ground, and they did that every time I faced them. I wasn’t good enough. It’s embarrassing on my end.”

“There's something about us they don't like, probably from my comments early in the year. They got more blood in the water, and they're hungry.”

Irvin clearly was not at his best, but Monday’s downfall did not fall squarely on him. After Irvin departed with a one-run lead, Deolis Guerra took over in the fourth and quickly allowed the Mariners to break through. Guerra gave up back-to-back RBI singles before surrendering a backbreaking three-run homer to Mitch Haniger, who slugged another three-run blast in the sixth to collect his third career multihomer game against Oakland.

The A’s are dangerously close to seeing their playoff hopes come to an end as early as Tuesday. As frustrating as the past week has been though, they remain committed to fighting until the end.

“Baseball is a crazy game,” Brown said. “Anything can happen. We’re looking to win out and do everything we can to give ourselves a chance. We’re going to keep digging and grinding it out. Our goal is to win every game, and we have these [final five] games ahead of us we need to capitalize on.”