SEATTLE -- For the second year in a row, the A's will be playing October baseball.

By virtue of the Indians' 8-2 loss to the Nationals on Friday, the A's clinched a spot in the American League Wild Card Game presented by Hankook Tire before even taking the field for the start of their game against the Mariners. Once their game began, the celebration got underway early as Marcus Semien and Matt Olson provided fireworks with a pair of home runs.

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But Liam Hendriks was unable to hold down a one-run lead in the ninth, surrendering a walk-off double to J.P. Crawford in a 4-3 loss. The defeat, however, was not enough to stop the A’s from popping champagne for an accomplishment that was eight months in the making.

“Would have liked to come out with the win, but this is more about the season in full,” Olson said. “It’s a moment we worked for since Spring Training. We’re going to celebrate, have fun, and come back tomorrow to try to keep it going.”

The A's know they'll be facing the Rays on Wednesday, but the venue for the 8:09 p.m. ET/5:09 p.m. PT matchup on ESPN is still up for grabs, as Oakland is now tied with Tampa Bay after Friday’s loss. The club must at least finish the regular season tied in order the secure home-field advantage for the AL Wild Card Game by virtue of winning the season series with the Rays, 4-3.

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There’s no atmosphere quite like a playoff game at the Coliseum, which usually consists of 58,000 screaming fans with a unique way of cheering, featuring drums beating throughout the bleachers and vuvuzelas to enhance the noise. The A’s want the AL Wild Card Game in Oakland.

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“We feel really confident at home, but no matter what the circumstance, in Tampa or Oakland, we’re going to be ready to play,” said A’s starting pitcher Mike Fiers, who pitched five innings of two-run ball on Friday. “It’s going to be a tough game, but obviously we’re hoping for Oakland.”

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Friday’s loss denied the A’s from tying their win total of 97 from 2018, but their 17 wins in September are still tied for their most in any month this year.

It’s been a season that saw a turnaround near the start of summer, when the A’s hovered around .500 through June 15, with a record of 37-35. But since then, their 59-28 mark is the best in baseball. If this sounds eerily familiar, that’s because it is -- in their 2018 run to the postseason, the A’s finished 63-29 from June 16 on, also the best record in the Majors in that stretch.

“Our guys wanted to win [tonight's] game and finish it out right. At the end of the day, we’re still going to the postseason. That’s all that matters,” A’s manager Bob Melvin said. “Come tomorrow, even though we got off to a little bit of a slow start in this party, they’re going to realize that. We’ve still got a little more to play for, but it’s been a terrific season, a lot like last season.”

In the Moneyball era, the A’s were always known to be a second-half team. Judging by the way the past two seasons have gone, this incarnation of players appears to be a throwback of sorts.

“That’s our team’s MO,” All-Star third baseman Matt Chapman said. “We start slow and take off at the right time. Just like how we get timely hits. We have a thing for the dramatics, I guess. We never quit, and that’s going to help us come October.”

Some considered Oakland's 2018 appearance in the AL Wild Card Game -- in which they lost, 7-2, to the Yankees -- to be a fluke. But the A's believe that they're only scratching the surface with an exciting young core expected to only get better over the next few seasons.

“It shows how good our team is. We’re a complete team,” Chapman said. “We don’t have a Mike Trout -- just a bunch of really good baseball players that really care about each other and have fun. I think this is going to be a trend. I’m hoping we can get a division title one of these years, but we’ll take the Wild Card for now and make the most of it.”

With the organization’s top three prospects -- Jesus Luzardo, A.J. Puk and Sean Murphy -- all contributing in major roles this season, along with two quality starting pitchers in Fiers and Sean Manaea, the A’s just might be better equipped to go on a postseason run.

“Two years in a row, we win 90-plus games. This year, in the mid-90s with a couple games to go, that’s something to be proud of,” Melvin said. “This group is establishing themselves as one of the better teams in the American League.”