Oakland's Esteury Ruiz had a solo homer and an RBI single and Ryan Noda also drove in two runs. Zack Gelof, Aledmys Diaz and Ruiz each had two hits to send the Athletics (44-97) to their fifth win in seven games.
Texas' Corey Seager clubbed a two-run homer and Nathaniel Lowe added an RBI single for the Rangers (76-64), who have lost four in a row and 16 of their last 20 games.
The Rangers didn't lose ground in the American League West race, as the first-place Astros (80-61) and the second-place Mariners (79-62) also fell on Friday. Texas trails Houston by three games and Seattle by 2 1/2 games.
Rangers right fielder Evan Carter went 1-for-3 with a walk in his major league debut. Carter was called up to replace Adolis Garcia, who sustained a patellar tendon strain during the Rangers' 12-3 loss to the Houston Astros on Wednesday.
Oakland's Kevin Smith hit a two-out double in the sixth inning and Langeliers deposited a first-pitch changeup from Jordan Montgomery (8-11) over the wall in center field. Langeliers' 17th homer of the season ended the evening for Montgomery, who allowed five runs on eight hits in 5 2/3 innings. The left-hander struck out six and walked one.
Noda added an RBI double in the seventh to benefit Devin Sweet (1-0), who recorded his first career major league victory after striking out two batters without surrendering a hit over two scoreless innings.
A's relievers Lucas Erceg and Dany Jimenez each worked a shutout inning to bridge the gap to Trevor May, who tossed a scoreless ninth to secure his 19th save of the season.
Oakland scratched for a run in the top of the first before Texas countered in its half of the first inning. The Rangers' Marcus Semien hit a leadoff single before Seager sent a 3-2 changeup from Paul Blackburn over the wall in right-center field for his 29th homer of the season.
Ruiz ripped an RBI single in the second inning to forge a 2-2 tie before the Rangers regained the lead in the fourth on Lowe's RBI single.
Ruiz leveled the contest at 3-3 while leading off the fifth, sending an 0-2 curveball from Montgomery over the wall in left-center field. The homer was Ruiz's fourth of the season and second in September.
—Field Level Media