With injuries to quarterbacks E.J. Manuel and Kevin Kolb, and with undrafted rookie free agent Jeff Tuel as the lone quarterback remaining on the depth chart, the Bills signed Matt Leinart on Sunday.
Manuel, the 16th overall pick in this April's draft, had minor surgery on his left knee and will miss the rest of the preseason while Kolb is dealing with concussion-like symptoms, which he suffered during Saturday's loss against the Redskins.
"Really excited and thankful for the @buffalobills for giving me the opportunity," said Leinart on his Twitter account. "Been working hard for 8 straight months. Time to go!!"
Leinart, selected by the Cardinals with the 10th overall pick in the 2006 draft, has spent the last three seasons as a backup with the Texans and Raiders.
In 33 career games, the former Heisman Trophy winner has completed 57.1 percent of his passes for 4,065 yards, 15 touchdowns and 21 interceptions.