The New York Mets traded Francoeur and cash to Texas for infielder Joaquin Arias, who was designated for assignment last week when Alex Cora was called up by the Rangers.
"I have an opportunity to go with a team that will be in the playoffs," Francoeur said. "I feel comfortable going out there."
The strong-armed Francoeur is hitting .237 with 11 homers and 54 RBIs and leads the NL with 11 outfield assists. Arias batted .276 in 50 games for the Rangers, including 22 starts. He had two stints on the disabled list.
Texas had been looking for a right-handed hitter to come off the bench for the final month of the season and its expected postseason appearance.
"He's another right-handed bat that we can get in the lineup against lefties," Rangers manager Ron Washington said. "We needed another right-handed bat and he'll give us that so that we don't have to keep sending up left-handed bats against the lefties. And he's a guy we know will drive in runs."
The deal had to be completed by midnight Tuesday in order for Francoeur to be eligible for the Rangers' playoff roster. Texas has an 8½-game lead in the AL West.
"I'm looking forward to it. I played with Frenchy in the WBC. He's a gamer. He always plays hard. He'll fit in well here," Rangers third baseman Michael Young said in Kansas City, where Texas lost 10-9 to the Royals.
In an interesting twist, the deal was completed while Francoeur was in Atlanta (he grew up in the suburbs) facing his original team, the Braves.
He looked like a hometown star during his first couple of seasons with the Braves, making the cover of Sports Illustrated as a rookie and twice driving in more than 100 runs.
But his production tailed off badly in 2008 and he was dealt to the Mets for little-used Ryan Church midway through last season. Francoeur had a promising half-season in New York, hitting .311 with 10 homers and 41 RBIs after the trade, but he slipped again at the plate this season and his playing time decreased despite his excellent defense in right field.
With the deadline approaching for playoff eligibility and the Mets out of contention, Francoeur was mentioned frequently in trade talk.
"Things happen for the best," he said. "It's been a tough couple of weeks for me. It just hasn't happened for me (with the Mets). People expect different things."
In addition to trading Francoeur, the Mets announced after a 9-2 loss to the Braves that two players, right-handed pitcher Jenrry Mejia and outfielder Lucas Duda, have been recalled from Triple-A Buffalo.
Mejia made 30 relief appearances for the Mets this season, going 0-2 with a 3.25 ERA. Duda hit .304 with 23 homers and 87 RBIs splitting time between Double-A Binghamton and Buffalo.
Teams can expand their rosters on Wednesday for the final month of the regular season.