Beauchemin appeared to crash into the boards in the second period. He played three shifts in the period and did not return.
"Right now it's day to day," Ducks coach Bruce Boudreau said after a 4-3 overtime loss to the Devils. "It just was an upper-body injury, but to lose him for any time is a big thing."
Beauchemin averaged 22:19 minute of ice time and is part of the top defensive pairing with rookie Hampus Lindholm. He had surgery to repair a torn ACL in the offseason and recovered in time for the start of the season.
"Hopefully he'll wake up tomorrow and he'll be better," Boudreau said.