Commentator Stephen A. Smith published a statement on his Web site Wednesday attributed to Iverson. It said Iverson plans to retire but also that "I feel strongly that I can still compete at the highest level."
The statement also said Iverson has tremendous love for the game and the desire to play.
"His legacy would be huge," Cleveland Cavaliers All-Star LeBron James said. "He's one of the best when you talk about guys 6-foot and under in the game of basketball. He played injured and he played hard every single night. I don't think it should end this way, but if it does, he's left a lot of great things behind."
The 10-time All-Star played three games this season with Memphis before taking a leave of absence to attend to personal matters. He was waived after the two sides agreed to part ways.
It was the second straight ugly ending for Iverson, who was unhappy last season playing for the Pistons. He was upset that Detroit coach Michael Curry and Memphis' Lionel Hollins used the former MVP as a reserve.
The New York Knicks considered signing Iverson last week after he cleared waivers, before deciding he would take too much playing time away from younger players they are trying to develop.
The Knicks seemed to be the only team who would consider bringing in Iverson, so there was no guarantee he'd play in the NBA this season, anyway. Still, the announcement Wednesday came as a surprise to George Karl, who coached Iverson in Denver.
"I think he still has something left to give some team out there. If that's his decision, he'll go down in history, I think, as the greatest little guard ever to play the game of basketball," Karl said.
"I was happy to have him for a couple years and hopefully our paths will cross. But I have a sneaky feeling that somewhere along the way an injury or a circumstance with a team will open that window back up."
One of the NBA's great scorers, Iverson entered this season with a career average of 27.1 points that ranked fifth all time. Yet there was almost no interest in him this summer before he went to the Grizzlies on a one-year deal.
Iverson can still score, as he averaged 17.4 points with the Pistons last season. Yet he has made it clear he doesn't view himself as a backup, which has likely hurt his chances of signing with a contending team.
The 6-foot guard thanked former players and coaches in the statement, plus the fans in Memphis and Philadelphia, where he spent his best years. He said stepping away would allow him to spend more time with his wife and kids.
He also said he thought he could still play after 14 seasons. "I always thought that when I left the game, it would be because I couldn't help my team the way that I was accustomed to," it read. "However, that is not the case."
Messages were left for Iverson's agent, Leon Rose, and his business manager, Gary Moore.
If this is the end for Iverson, he leaves with four scoring titles and a playoff scoring average of 29.7 points that ranks second only to Michael Jordan. He led the 76ers to the 2001 NBA finals but never won a championship.
Or he could choose to wait and see if a team in need of a scorer comes looking for him later this season.
"I don't ever believe anyone retires until they get to the point they have to," Boston coach Doc Rivers said. "He had a great career if it is true, but I still think he has more to offer."