CLEVELAND (AP) The most frustrating season of Joe Haden's career is over.
Six weeks after sustaining his second concussion, the star cornerback was placed on season-ending injured reserve Monday by the Browns, whose defense was thrown into turmoil after losing its best player.
Haden, who appeared in only five games, has been sidelined since sustaining his second concussion on Nov. 1 against Arizona when he was accidentally kicked in the head as he tried to make a tackle. The 26-year-old received his first concussion on Oct. 11 when he was knocked down while trying to make an interception against Baltimore.
Haden struggled to be cleared in the NFL's concussion protocol and the Browns reluctantly placed him on IR.
''This has been an extremely difficult season for me personally,'' Haden said in the team's release. ''It's upsetting that my year has ended this way. I really want to be out there with my teammates trying to help finish this season strong and on a positive note. We've all learned how important it is to be very thorough with concussions and I appreciate the care the Browns have provided for me.''
Haden added that specialists expect a full recovery.
''I'm looking forward that, returning to form, having a good offseason and an even better 2016 season,'' he said.
Haden has been named to the Pro Bowl the past two years. While he wasn't playing up to his usual high standards early on this season, he's still regarded as one of the NFL's top cover cornerbacks and his loss had a ripple effect through Cleveland's defense.
Haden signed a five-year, $68 million contract before last season. The Browns selected him with the No. 7 overall pick in the 2010 draft.
Browns coach Mike Pettine indicated last week that Haden was likely to go on IR and said wide receiver Andrew Hawkins could as well. Like Haden, Hawkins has suffered two concussions in 2015 and has missed a total of five games, including the past three.
Wide receiver Taylor Gabriel just resumed practicing after missing two games with a concussion and cornerback Justin Gilbert remains sidelined with a head injury.
''I think Joe is as frustrated as anybody else,'' Pettine said. ''I just know he's very frustrated and wants to be out there with his teammates.''
Haden played 15 games in each of the past two seasons. He was suspended four games in 2012 for violating the league's policy on performance-enhancing substances.
In other moves, the Browns claimed offensive lineman Kaleb Johnson off waivers from Baltimore and signed wide receiver Rannell Hall off Tampa Bay's practice squad.
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