The 6-foot-2 inch junior from Westlake, Calif., has been limited in practice by a sprained right thumb.
Coach Dennis Erickson told the Arizona Republic that sophomore backup Danny Sullivan is ready in case Carpenter can’t play.
For the season, Carpenter has completed 149 of 228 passes for 1,949 yards with 17 touchdowns and seven interceptions, while the unbeaten Sun Devils (8-0, 5-0 Pac-10) have risen to No. 6 in the latest USA Today coaches poll.
"This is going to be our true test because it's going to be on the road (at Eugene, Ore.) and probably the toughest stadium to play in Pac-10," Erickson said earlier this week.
Carpenter suffered the injury last Saturday night in ASU’s 31-20 victory over California, and threw a pass for the first time on Wednesday after being limited to handoffs.
"He threw pretty good," Erickson told the Republic.