McCarron, who turns 30 in September, played in only two games for the Houston Texans in 2019: mop-up duty in a blowout loss to the Ravens and when Houston rested its starters in Week 17.
In those games, he completed 21 of 37 passes for 225 yards and one interception.
The former Alabama quarterback spent his first four NFL seasons with the Cincinnati Bengals, starting three games. Before joining the Texans, he spent the 2018 season with the Oakland Raiders as backup to Derek Carr.
McCarron has played in 15 NFL games, making four starts, and has completed 62.4% of his passes for 1,153 yards, 6 touchdowns and 3 interceptions.