By MIKE McLAIN Tribune Chronicle BEREA — The knee injury that ended the season for tight end Steve Heiden could signal the end of his eight-year stay with the Browns. Heiden will turn 34 shortly after the start of the 2010 season. He’s battled knee and back injuries in recent seasons. If the Browns have a new coach next season, it’s possible Heiden might not be part of the plan. Coach Eric Mangini isn’t certain that Heiden’s playing days are done. “He’s disappointed that it went the way that it did,” Mangini said. “He’s worked incredibly hard to play this season, and he’ll work equally as hard this offseason to get back. I see him being ready to go next season.” The loss of Heiden is a hit at a position that lacked quality depth from the first day of training camp. Robert Royal has been injured and has just nine receptions for 100 yards and one touchdown. Greg Estandia was signed after the second game but has been inactive each week he’s been with the team.