Amano left the field holding his arm -- the one he uses on snaps -- and was escorted to the locker room.
"He got it caught. I think a helmet hit, but I'm not sure," coach Mike Munchak said. "A lot of times once the soreness settles down, it's not an issue."
Amano is fighting for his starting job with Kevin Matthews, who sat out practice because of concussion symptoms. Fernando Velasco, battling for the starting right guard spot with Leroy Harris, finished the practice at center.