Corey Seager launched a two-out, two-strike, three-run home run in the eighth inning Monday night, rallying the visiting Texas Rangers to a 4-2 victory over the Oakland Athletics in the opener of a four-game series.

A pair of sacrifice flies had the A’s in front 2-0 in search of the seventh win in eight games before pinch hitter Josh Smith led off the Texas eighth by drawing a walk off Oakland’s third pitcher, Lucas Erceg (1-2).

A one-out single by Leody Tavares put two on, and after Marcus Semien lined out, Seager cleared the wall in center field for his third homer of the season.

Protecting a one-run lead, David Robertson threw a 1-2-3 bottom of the eighth before Kirby Yates, given an extra run of cushion, pitched around a one-out walk in the ninth for his sixth save.

An error by A’s first baseman Tyler Nevin allowed Evan Carter, who had walked, to score the insurance run in the top of the ninth.

Jose Leclerc (3-2), who finished off a scoreless seventh after JJ Bleday doubled against Rangers starter Andrew Heaney, was credited with the win.

Darell Hernaiz and Esteury Ruiz drove in runs for the A’s.

Hernaiz’s sacrifice fly came in the second after singles by J.D. Davis and Abraham Toro, then a Shea Langeliers fly ball that advanced Davis to third.

Ruiz made it 2-0 in the fifth after an error on left fielder Ezequiel Duran put Bleday on first. Bleday went to third on a single by Brett Harris and then scored on the sacrifice fly.

Heaney yielded two runs (one earned) on seven hits in his six-plus innings. He struck out five and did not walk anyone.

Fellow veteran left-hander Alex Wood also went six innings before leaving with a 2-0 lead. He allowed two hits and one walk while striking out three.

The home run by Seager was the only extra-base hit of the game for the Rangers, who won their third straight game.

The hot-hitting Toro collected a double and two singles, and Davis chipped in with a pair of singles for the A’s, out-hit the Rangers 7-5.