League sources told NFL Media that Newton sustained a slight bone bruise in his right hand after banging it on a helmet. According to ESPN, the injury isn't considered serious but could limit his participation until training camp.
The Patriots are scheduled to have four more voluntary OTAs next week and then three days of mandatory minicamp after that. Newton could be shut down for those practices as the team prepares for the start of training camp in late July.
Newton, who didn't take part in the remainder of Friday's practice after the injury, stayed on the field to watch the rest of the session. First-round draft pick Mac Jones, third-year player Jarrett Stidham and veteran Brian Hoyer took the repetitions in place of Newton.
The 32-year-old Newton -- a three-time Pro Bowl selection -- recorded 2,657 passing yards with eight touchdowns and 10 interceptions in 15 games last season. The 2015 NFL MVP added 592 yards and 12 scores on the ground in 2020.
When the Patriots selected Jones with the No. 15 overall pick in April's NFL Draft, head coach Bill Belichick made it clear that Newton was still the team's starter at quarterback.
"Cam's our quarterback," Belichick said. "Whatever position, whatever time Jarrett or Mac are ready to challenge and compete, then we'll see how that goes."