Because the two teams completed the deal before Tuesday evening's postseason roster deadline, Francoeur will be eligible to play for the Rangers in October.
Francoeur, acquired from the Braves last June for outfielder Ryan Church, hit merely .237 with 11 home runs for the Mets this season, starting the year as the primary right fielder but eventually losing the job to Angel Pagan. With the Rangers, who are almost certain to make the playoffs, he will become a right-handed bat and defensive replacement off the bench.
It was a rapid demise for Francoeur, whom the Mets considered signing to a long-term extension around this time last year. But by this July, he had become little more than a platoon outfielder. Because he will be due more than $5 million in arbitration next year, the Mets would have non-tendered him after the season.
"They're not going to need me as a fourth outfielder," he said. "This is an opportunity for me to go play for a World Series."
Francoeur, whose best asset is his throwing arm, has been to the postseason just once in his six-year career, back in his rookie season, 2005, with the Braves.
"I didn't envision the year going the way it did for me -- personally and for the team," he said. "But at the same time, I feel that I came out to play hard every day. Sometimes it wasn't the best, and sure I got frustrated, but this is going to be a good opportunity for me to go play against some lefties and go to the playoffs."
The move was not a salary dump for the Mets, who will pick up most of Francoeur's remaining salary. Instead it was an attempt to receive something of value for a player they were not going to retain anyway.
Arias, 25, played sparingly for the Rangers this year, hitting .276 with a .290 on-base percentage and a .347 slugging percentage in 98 at-bats -- the bulk of them before the All-Star break. But the Mets are intrigued by what he may be able to provide.
"He's a young middle infielder who we have good reports on," assistant general manager John Ricco said. "A guy who we think has some upside. He's got some big-time tools."
Though Francoeur's departure is not altogether surprising, it is still somewhat shocking for a group of Mets who have embraced him over the past year as a clubhouse leader. Francoeur's outgoing personality won him many friends among his teammates and coaching staff, despite his shortcomings as a player.
Those relationships are what will stick with him the most.
"There's tons I'm going to miss, man," Francoeur said.
"Frenchy's a person of great character and great leadership skills," manager Jerry Manuel said. "Those are some of his greatest assets."
Before leaving Turner Field on Tuesday, Francoeur received handshakes and hugs from many of his teammates. He stopped for a long chat with third baseman David Wright and hitting coach Howard Johnson, with whom he is particularly close.
"I wish everybody on this team the best," Francoeur said. "I have so many good friends here and so many guys that I respect, and hopefully they can get it turned around."