Palmer, who practiced fully on Wednesday, does not appear to be in danger of missing Sunday's game against the Cleveland Browns. Raiders offensive coordinator Greg Knapp said he was 100 percent confident Palmer would be fine for Sunday.
Raiders head coach Dennis Allen said Palmer's thumb was "a little sore" on Thursday, which is why the Raiders decided to limit his snaps. Palmer originally injured his thumb when he hit it on a helmet on a pass attempt against the Bengals.
Palmer has started all 11 games this season. He's thrown for 3,181 yards and 18 touchdowns. Palmer's injured thumb may have affected him against the Bengals, as he threw for a season-low 146 yards. Matt Leinart is listed as Palmer's backup, although it's possible the Raiders could also turn to Terrelle Pryor if Palmer is unable to play.