(CNN) - So much for an early retirement.
Despite claiming he "will not be playing in the NFL anymore" in a tweet posted in September, wide receiver Antonio Brown is working out with the New Orleans Saints.
Brown posted on his Instagram account a waiver form with the Saints, and he posted some videos from inside the team's facilities.
But all of this could be for naught.
The NFL has confirmed to CNN that it is still investigating allegations against Brown, and the NFL has already threatened to place Brown on the commissioner's exempt list if he is signed by a team.
The exempt list prevents a player from attending practice or games, and only allows players inside facilities for meetings, individual workouts and other non-football activities.
"As long as Mr. Brown is a free agent, placement on the Commissioner's exempt list is not appropriate," the league said in a statement. "If he is signed by a club, such placement may become appropriate at any time depending on the status of the investigation. Upon the conclusion of the investigation, he may also be subject to discipline if the investigation finds that he has violated the law or league policies."
So, even if the Saints decided to offer Brown a contract to play with the team, the league could prevent Brown from suiting up.
Brown's agent, Drew Rosenhaus, declined to comment to CNN.
Brown has had a tumultuous year. He was traded by the Pittsburgh Steelers to the Oakland Raiders in March, where he was eventually cut after clashing with Raiders general manager Mike Mayock.
He then signed a one-year deal with the New England Patriots, but he was cut after playing in one game following accusations of sexual misconduct in a Sports Illustrated story.
The Saints are projected as the third seed in the NFC with a 12-3 record. Adding a player of Brown's caliber to their already potent offense alongside star receiver Michael Thomas would make the Saints one of the most dangerous teams entering the playoffs.
But that's only if he's allowed to play.
CNN's Kevin Dotson and Eric Levenson contributed to this story.