BEREA, Ohio — Cleveland's quarterback curse claimed another victim.

Robert Griffin III will miss at least eight games — and potentially the season — after breaking a bone in his left shoulder during his regular-season debut with the Browns on Sunday.

Griffin, who signed with the Browns as a free agent in March, got hurt while trying to run out of bounds in the fourth quarter.

He stayed in the game, but an MRI on Monday revealed that he broke a coracoid bone in his shoulder. Griffin does not need surgery at this time, but will be evaluated in 3 to 4 weeks.

The Browns placed Griffin on injured reserve — under new NFL rules he can brought off the list — and could return at some point in 2016.

"It's very unfortunate, Robert came in and has worked extremely hard to learn our offence and earn the respect of his teammates," Browns coach Hue Jackson said.

"This is a tough loss because everyone has seen how invested he has been in this team and his dedication to the work needed to improve his craft. We all know these are the realities of the NFL, injuries occur and you have to find ways to overcome them so they don't impede your progress."

The 26-year-old Griffin returned to the game for Cleveland's final series, but only handed the ball off while favouring his left arm. RG3 is the 25th quarterback to start for the Browns since 1999, a roll call of rookies, veterans and free agents.

Adding insult to injury, the Browns were beaten on Sunday by Eagles rookie quarterback Carson Wentz, a player they passed on taking and traded the No. 8 overall pick to Philadelphia.

With Griffin out, Josh McCown will start this week's home opener against Baltimore. McCown, who coincidentally sustained a concussion in his debut with Cleveland, made eight starts for the Browns last season and passed for 457 yards in a win over the Ravens.

McCown was involved in trade rumours during the off-season, but the Browns are glad he's still around.

"That's why we kept him here." Jackson said. "We have a very capable backup. He knows how to play."