OAKLAND -- The A’s had no doubts about Chris Bassitt -- September’s American League Pitcher of the Month -- showing up big in the most important game of the year. The onus was going to fall on the offense to provide him with support.

After mustering just three hits in a Game 1 loss that saw them stifled by Lucas Giolito, Oakland’s bats came roaring back. Homers by Marcus Semien and Khris Davis supplied more than enough cushion for Bassitt, who was brilliant in his postseason debut with seven-plus innings of one-run ball in Wednesday's 5-3 victory over the White Sox in Game 2 of the AL Wild Card Series at the Coliseum.

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But the A’s had to sweat it out in the ninth. The White Sox forced closer Liam Hendriks -- who entered the game in relief of Bassitt in the eighth -- out of the game in the ninth and loaded the bases. Jake Diekman took over for Hendriks, and though he walked in a run, the left-hander closed it out by retiring José Abreu on a ground ball to second base.

Though Hendriks threw 49 pitches, A’s manager Bob Melvin said he expects the right-hander to be available out of the bullpen for Game 3.

“We won. That’s all that matters,” Melvin said. “It wasn’t comfortable. But we did just enough offensively to win and Bassitt was terrific.”

The win conquered some playoff demons for the A’s, who snapped a six-game losing streak in the postseason with their first playoff win since Game 4 of the 2013 AL Division Series against Detroit. Forcing a deciding Game 3 for Thursday at the Coliseum, they also broke a run of nine straight losses in elimination games that began after their Game 7 win in the 1973 World Series against the Mets.

“I think there’s relief,” Bassitt said. “We knew the numbers. I feel like the monkey’s off our back a little bit and now we can just play baseball from here on out. We were excited, but relieved more than anything.”

Before the game, Melvin stressed the importance of scoring early after they went without a hit or walk until the seventh inning of Tuesday’s 4-1 loss in Game 1. The A’s responded by jumping on White Sox starter Dallas Keuchel with four runs through the first two frames, including Semien’s two-run blast -- a booming drive that sailed 418 feet to straightaway center for his first career postseason home run -- in the second.

Davis’ second career postseason homer -- a solo shot to lead off the fourth -- spelled the end for Keuchel, who was chased after just 3 1/3 innings.

“It seems like we’ve had a lot of games where it’s just zeros first time through the lineup and we get a hit that wakes us up,” Semien said. “A lot of times, it’s a home run. It seemed like guys were all over Keuchel in the first inning. I thought that was the right approach, and that’s what I took into the at-bat.”

The four-run lead after two allowed Bassitt to work through some early command issues. Following back-to-back singles to lead off the third, Bassitt received a major assist from Mark Canha, who timed a fly ball from Yoan Moncada perfectly for a leaping catch at the left-field wall.

Canha’s catch may have harkened back some memories for longtime A’s fans of another famous catch that took place in Oakland nearly 50 years ago, when Joe Rudi leaped at the Coliseum wall to make a great catch in Game 2 of the 1972 World Series.

Melvin, a Bay Area native who grew up watching the A’s, certainly had flashbacks of the famous play as he watched Canha hit the wall.

“That was exactly what I thought when he caught that ball,” Melvin said. “It’s almost an identical play. Just a different wall. This one is padded. I don’t think it was padded back then.”

Canha, also a Bay Area native of San Jose, was quickly introduced to the play after checking social media in the clubhouse.

“Somebody put a side by side on Twitter,” Canha said. “It’s pretty cool to be compared to that. Let’s hope we can get to the World Series and I’ll make another one.”

Perhaps fueled by the clutch defensive play, Bassitt seemed to find another gear, retiring the next 11 batters he faced after the catch.

Completing seven shutout innings, Bassitt went back out for the eighth but was quickly pulled after a leadoff single by Tim Anderson. He finished allowing one run on six hits and a walk with five strikeouts over seven-plus innings, with the one run scoring on a two-run homer given up to Yasmani Grandal by Hendriks in relief.

There was plenty of reason to believe Bassitt was capable of this type of performance given the numbers -- his 2.29 ERA in the regular season was third lowest among AL starters. But the postseason is a different animal, as Bassitt attested to after the game when he admitted to having a faster heart rate than usual. Still, he maintained his composure to continue what has been a strong run in the month of September.

“Bass has been the same guy all year,” Semien said. “He didn’t let the playoff nerves get to him at all. He was the same guy with the same stuff. First inning, he came out amped up and his velocity was up. Then he calmed down and made sure he made his pitches.

“I’m proud of him and happy we’ve been playing together since we got drafted. Just to be on that stage with him and see him do well was amazing.”

In 33 2/3 innings this month, Bassitt has allowed just two runs. But no innings were more impressive than his seven-plus against Chicago.

“That was probably the game of his life,” Melvin said. Bass ended up giving us a lot today in a game where we needed it. He’s been waiting for that game his entire life and he responded really well.”

Getting that first playoff win since 2013 out of the way, the A’s will now look to finish the job in another win-or-go-home Game 3. Neither club has announced a starting pitcher for Thursday, though the A’s are likely to start a right-hander, likely Mike Fiers, given Chicago’s 15-0 record against lefties this year.

“For a lot of guys in here, this is our first playoff win. It feels good,” Semien said. “We’re hungry for more wins. Tomorrow, anything can happen. It’s just like Game 7. We want to just play our game and have a good plan against whoever we face and see what happens.”