Coach Bruce Arians had confirmed Tuesday that the team was working to sign Gabbert, who had played for Arians with the Arizona Cardinals in 2017.
Gabbert, 29, played one season for the Titans, appearing in eight games and starting three, including the 2018 season finale against the Indianapolis Colts in which the winner clinched a playoff berth. Gabbert won two of his three starts, but the Titans lost that game to Indianapolis to end their season. He finished the season throwing for 626 yards with four touchdown passes and four interceptions and completing 60.4 percent of his pass attempts.
He has appeared in 56 games, with 48 starts, since the Jacksonville Jaguars selected him 10th overall in the 2011 draft.
Gabbert, who also has played for the San Francisco 49ers, has thrown for 9,063 yards with 48 touchdown passes and 47 interceptions and a 56.2 percent completion percentage in his career.