OAKLAND, Calif. -- The math is becoming simpler and the task more daunting every day for the Texas Rangers in their quest for an American League wild-card playoff berth.

The Rangers lost for the second straight night to the last-place Oakland Athletics, this time 1-0 on Saturday night at the Oakland Coliseum.

Texas (76-78) fell 4 1/2 games behind the Minnesota Twins, 10-4 winners over Detroit, for the second wild-card spot. The Rangers, who have eight games remaining, are tied with Kansas City and the Los Angeles Angels.

"We got to win tomorrow," said Rangers bench coach Steve Buechele, who served as acting manager in place of Jeff Banister. Banister returned to Texas to be with his mother, Verda, who is having complications from a recent surgery. "We're going to take one game at a time, not look ahead. We know exactly where we're at. We got to win the games."

That hasn't been easy for the Rangers at the Coliseum this season. Khris Davis hit his 40th home run of the season, Raul Alcantara threw five strong innings and the A's beat Texas at the Coliseum for the seventh straight time. The A's (71-83) won their season-high sixth straight game overall.

"It is tough," Rangers shortstop Elvis Andrus said. "But there's no other way to go. We have to come back tomorrow and win. We're having a tough time winning here. Winning tomorrow and heading back home would be really good."

Davis became the second Athletic in franchise history to hit at least 40 home runs in back-to-back seasons, joining Jimmie Foxx (1932-34). Davis hit a career-high 42 home runs last season, his first with Oakland. With his solo shot in the second inning, Davis also set a career high for RBIs with 103, one more than he had last year.

"It's nice to be mentioned in the presence of Hall of Famers," Davis said. "I'm just enjoying it and embracing it as much as I can, just trying to help the ballclub win games."

Alcantara (1-1) made a spot start in place of lefty Sean Manaea, who was a late scratch because a strained upper back. Alcantra allowed no runs on two hits over five innings with five strikeouts and two walks. He lowered his ERA from 9.20 to 6.86.

Alcantara made a spot start at Detroit on Monday and blanked the Tigers for 3 2/3 innings on two hits in an 8-3 Athleitcs' victory.

"He looks like a different guy," A's manager Bob Melvin said of Alcantara. "I think a lot of it had to do with how well he pitched last time. The command of the fastball is better. It looks to me like his split and slider are better, and he's pitching with a lot more confidence. It's good to see."

Ryan Dull, Daniel Coulombe, Chris Hatcher and Blake Treinen combined to blank Texas over the final four innings on two hits. Treinen pitched a scoreless ninth for his 11th save.

Rangers right-hander Miguel Gonzalez (8-12) allowed one run on four hits over six innings in his fourth start since being traded by the White Sox to Texas. He struck out five and walked none.

The Athletics took a 1-0 lead in the second inning when Davis led off with his milestone home run. Davis launched Gonzalez' first-pitch fastball over the right-center field wall.

"First pitch, you tip your hat to him," Gonzalez said. "He's a great hitter. It's a young team and I know they're going to be aggressive, starting from the get-go. I thought it was a good pitch. Maybe just up a little bit."

After Davis' home run, the A's loaded the bases as Matt Olson and Ryon Healy singled, and Matt Chapman was hit by a pitch. But Gonzalez retired the next three batters to escape further damage.

The Rangers had runners on first and second with two outs in the fifth after Robinson Chirinos singled and Alcantara walked Rougned Odor. But Alcantara retired Drew Robinson on a ground ball to end the threat.

"Not to complain or anything, but the last couple games were typical games for us in Oakland where you look up there and we have three, four hits in the middle of the game and we don't bunch them together, we don't make any productive outs," Buechele said. "We have a tough times stringing hits and having that big inning here in this ballpark."

NOTES: A's C Bruce Maxwell became the first Major League Baseball player to kneel during the national anthem as he joined a protest against racial injustice that former San Francisco 49ers quarterback Colin Kaepernick began last season. Maxwell is an African American who was born in Wiesbaden, Germany, when his father, Bruce, was stationed there with the Army during a tour of duty. Maxwell posted a strong response on Instagram opposing President Trump's recent criticism of NFL players who kneel during the anthem. A's OF Mark Canha placed a hand on Maxwell's shoulder during the anthem then hugged him when it ended. "My kneeling, the way I did it was to symbolize the fact that I'm kneeling for a cause, but I'm in no way or form disrespecting my country or my flag," Maxwell. said. Maxwell missed his second straight game while undergoing concussion tests. ... Rangers manager Jeff Banister returned to Clear Lake, Texas, before Saturday's game to be with his mother, Verda, who is experiencing complications from recent surgery. Banister is expected to miss Sunday's series finale, too. Bench coach Steve Buechele filled in for Banister on Saturday in his first full game managing in the big leagues and will fill in again Sunday. "We'll just hold down the fort until he's back," Buchele said. ... A's INF/OF Chad Pinder (sore back/neck) was out of the lineup, one day after crashing into the right-center field wall in the sixth inning while trying to catch a deep fly ball.