Cleveland running back William Green has had his suspension extended indefinitely.
Green absence has not helped Cleveland's struggles
Green was suspended on 8 November for four games for violating the NFL's substance-abuse policy.
He was arrested in late October and charged with reckless driving, driving under the influence and possession of marijuana.
Green, 23, was enrolled in the second stage of the league's treatment programme and had been due to return for the Browns against St Louis on 8 December.
But the NFL said Tuesday that Green would remain suspended for "treatment purposes".
A decision on his return will be made after NFL commissioner Paul Tagliabue has consulted medical experts.
Green had been Cleveland's leading rusher this season, with 599 yards before his suspension began. The Browns are now struggling at 4-8.
His fiancee, Asia Gray, 22, pleaded not guilty last month to charges that she stabbed him during a fight at their home.