Heavy rainfall forced Saturday's game to be postponed until Sunday. The Rangers began the day with a magic number of one to lock up at least an American League Wild Card spot.
Regular starters normally get a game off during a doubleheader, but Rangers manager Ron Washington had no such plans.
"Not on Sept. 30," he said.
Washington put his regulars in the lineup against the Angels' Zack Greinke in Game 1. Yu Darvish was in position for his 17th win after a solid 6 2/3 innings, but Torii Hunter's two-run double off Joe Nathan in the ninth gave the Angels a 5-4 victory.
That decreased the Rangers' AL West lead to two games over the A's and kept their magic number for a third straight division title at three. The A's are playing the Mariners on Sunday afternoon.
The Angels pulled within two games of Oakland for the final Wild Card spot and will start Ervin Santana in Game 2, against the Rangers' Derek Holland. First pitch is set for 7:05 p.m. ET, in the first split doubleheader the Rangers have ever played at home.
Holland has not lost in 10 starts since the beginning of August, going 4-0 with a 3.78 ERA over that stretch. He lasted only three innings in his last start, giving up three runs on four hits in a 5-4 Texas win over the A's on Monday.
Santana has lasted at least six innings in each of his last nine starts, going 4-2 with 2.88 ERA over that span. He pitched less than six innings in eight of his previous 11 starts, a stretch that saw him go 3-4 with a 7.83 ERA.
Angels: Morales returns from rib soreness
Kendrys Morales was not in the Angels' lineup on Saturday before their game against the Rangers was rained out. A sore rib cage that has bothered him over the last couple of days, along with the fact that left-hander Holland was set to start, would have kept him from starting. Morales, who struck out three times in Friday's series opener, started Game 1 of Sunday's doubleheader and went 0-for-4 with an RBI.
"We really need him from the left side," Angels manager Mike Scioscia said on Saturday. "That's where it was affecting him a little more last night."
Rangers: Perez set to start on Monday
If he is not used out of the bullpen during Game 2 on Sunday, rookie Martin Perez will start Monday's series opener against the A's.
Perez has lost both of his starts since being called up from Triple-A Round Rock on Sept. 1, and gave up five runs on six hits in two-thirds of an inning of a 9-3 loss to the A's on Wednesday.
"If we don't use him out of the bullpen this weekend, then he's the guy on Monday," Washington said. "But we've got to get through these two games, and everybody is on deck."
Adrian Beltre, 33, hit his 36th home run of the season on Friday while Josh Hamilton, 31, holds the team lead with 43 homers. This makes the Rangers the seventh team in Major League history with two players at least 31 years old to hit 36 home runs in the same season.
Rangers right-hander Koji Uehara tossed a perfect ninth inning on Friday night and has not allowed a baserunner in a team-record eight consecutive appearances. He's struck out 12 over 6 2/3 innings during that stretch.