Washington Redskins quarterback John Beck is suffering from some soreness in his throwing arm, coach Mike Shanahan said Tuesday.

Beck has taken the bulk of the first and second-team snaps in training camp because he is the only veteran able to practice.

The Redskins have two undrafted rookie quarterbacks – Indiana’s Ben Chappell and UVA’s MarcVerica – on the roster, but their knowledge of the plays is limited. The team signed free agent Kellen Clemens last Wednesday, but he isn’t allowed to practice until Aug. 4.

Beck has struggled with accuracy when going deep this week, but previously had been sharper on shorter passes. Tuesday, however, he often threw balls behind receivers and underthrew others.

“Even though John’s gotten a lot of reps, his arm is a little sore today. I could see it,” Shanahan said. “He didn’t quite have the zip on it that he normally has. So therefore, you don’t want to set him back at all, so you have to be very careful.”

Grossman’s arrival on Thursday should help spare Beck some wear.

Shanahan said he hadn’t yet decided how he would handle divvying up playing time in the preseason opener Aug. 12.