The Oakland Raiders signed veteran quarterback J.P. Losman on Tuesday as an insurance policy in light of knee injuries to starter Bruce Gradkowski.

Raiders coach Tom Cable said Monday that Gradkowski is doubtful for Sunday’s game against the Denver Broncos. Gradkowski suffered medial collateral ligament tears in each knee last Sunday against the Washington Redskins.
If Gradkowski is unavailable, Cable is faced with the prospect of choosing from among Losman, JaMarcus Russell and Charlie Frye as his starter.
Losman, 28, is fresh from guiding the Las Vegas Locomotives to the UFL championship under the guidance of coach Jim Fassel, whose son John is the Raiders special teams coordinator. Jim Fassel attended the Redskins game on Sunday.
Losman spent the past five seasons with the Buffalo Bills, where he started 33 games. Sixteen of those starts came in 2006, when he completed 62.5 percent of his passes and recorded 19 touchdowns, with 14 interceptions. Overall, Losman amassed 33 touchdowns and 34 interceptions in 42 games with the Bills.
Losman turned down opportunities for a backup role in the NFL this season so that he could get playing time in the UFL. Rick Mueller, the general manager of all four UFL teams, said that’s a path many players will look at taking in future years.
“Players can come into the league and actually play a full season,” Mueller told FanHouse.com. “There is a chance to be a starter and lead a team, and guys like ... J.P. took full advantage.”
In other news, the Raiders waived guard Roy Schuening and signed offensive tackle Elliot Vallejo to their practice squad.