Choo, who also scored the tying run in the seventh, reached base for the fourth time on a walk to start the ninth against Phillies left-hander Mario Hollands (0-1), who was making his major league debut.
After Elvis Andrus' sacrifice bunt and walk to Prince Fielder, Phillies manager Ryne Sandberg went to right-hander B.J. Rosenberg. Beltre singled softly to right-center field, scoring Choo without a throw.
New Texas closer Joakim Soria got the win with a perfect ninth inning in his season debut.
The first replay review of the series was a successful challenge by Rangers manager Ron Washington and helped keep a run off the board in Philadelphia's two-run sixth inning.
Philadelphia's Ben Revere was initially called safe at second base by Cory Blaser on a pickoff attempt by Martin Perez. Washington asked for the review, which showed second baseman Donnie Murphy's glove on Revere's back as he caught the ball before a diving Revere's hand was back on the bag.
Revere would have scored on Ryan Howard's double later in the inning, but instead only Jimmy Rollins came home for a 2-0 lead. Rollins broke the scoreless tie with a single.
Washington decided against a challenge moments before the reversal. Jim Joyce called Cesar Hernandez safe at third on a sacrifice bunt by Revere, and Washington came out to talk to the crew chief but didn't challenge. Replay showed the call was correct.
Mitch Moreland's single got the Rangers within 2-1 in the sixth, and Beltre had a tying double with two outs in the seventh to score Choo, who had two singles and was hit by a pitch before his ninth-inning walk.
Perez had seven strikeouts through five shutout innings but didn't make it through the sixth, giving up hits to four of the six batters he faced in the inning.
Howard batted fifth for the Phillies, snapping a streak of 665 straight regular-season starts as the cleanup hitter dating to June 29, 2008, also against the Rangers. He went 1 for 4 with two strikeouts, including one with two runners on in the eighth inning after the Rangers intentionally walked Marlon Byrd.
Philadelphia's A.J. Burnett left with a 2-1 lead after six innings in the debut for his fifth team covering 16 seasons. The 37-year-old right-hander gave up seven hits with two walks and three strikeouts.
NOTES: Rangers RHP Colby Lewis threw 92 pitches in a minor league exhibition game for Frisco as he continues his comeback from hip surgery. He gave up five runs in 5 1-3 innings. ... The Rangers tweeted an apology after a picture circulated from opening day showing dozens of empty beer cans and bottles at the base of a statue honoring Shannon Stone, the firefighter who died in a fall at the Rangers' home stadium in 2011. The team said the debris was removed "in a timely manner but it should not have been allowed to be placed there in the first place