"After careful thought and deep consideration I've decided that I need to step away from pursuing my return to the Browns and my football career to enter an in-patient rehabilitation facility," Gordon wrote. "This is the right decision for me and one that I hope will enable me to gain full control of my life and continue on a path to reach my full potential as a person. I appreciate the support of the NFL, NFLPA, the Browns, my teammates, my agent and the community through this extremely challenging process."