Gee, 29, had the right to opt out after the completion of the regular season because he had more than three years of MLB service and did not return to the majors after being outrighted to Triple-A Las Vegas during the season.
Originally drafted in the 21st round in 2007 out of Texas-Arlington, Gee finished his Mets career with a 40-37 record and 4.03 ERA in 114 appearances (110 starts).
Despite being the Opening Day starter in 2014, the Mets treated him awkwardly this year. With Matt Harvey back from Tommy John surgery, Gee worked out of the bullpen early in Grapefruit League play during spring training. When Zack Wheeler required Tommy John surgery, Mets officials did not immediately place Gee back in the rotation. They instead had him compete with Rafael Montero.
Once Gee went on the disabled list with a groin injury and Noah Syndergaard arrived in the majors, Gee's role again became up in the air. He had an elongated rehab assignment, ever so briefly was part of a six-man rotation, then finally was designated for assignment on June 15.
Gee ultimately went 0-3 with a 5.90 ERA in eight appearances (seven starts) this season at the major league level.
Because Gee made $5.3 million this season, he would have been non-tendered on Dec. 2 had he not elected free agency.
Also becoming free agents across MLB through the same process are: Jeff Bianchi, Reid Brignac, Angel Castro, Casey Coleman, Ernesto Frieri, Conor Gillaspie, Javy Guerra, Brandon Kintzler, Michael Kohn, Steve Lombardozzi, Alfredo Marte, Justin Maxwell, Bradley Mills, Hunter Morris, Hector Noesi, Sean O'Sullivan, Jordan Pacheco, Andrew Parrino, Vinnie Pestano, Yohan Pino, Alex Presley, Todd Redmond, Michael Roth, Jhontan Solano and Everett Teaford.