NBA legend Charles Barkley has warned Allen Iverson that he must accept he can no longer be the main man on a team if he returns to basketball.

Iverson, 34, announced his retirement form the sport on Wednesday to bring the curtain down on a 14-year career that saw him crowned the league's Most Valuable Player in 2001 and voted an NBA All-Star 10 times.

The shooting guard, who led the Philadelphia 76ers to the 2001 NBA finals, is understood to have decided to retire after failing to find a new team since being released by the Memphis Grizzlies on November 17, although many in the game, including former coach Larry Brown, have urged Iverson to reconsider.

Since leaving Philadelphia in 2006, Iverson has played with the Denver Nuggets but joined the Detroit Pistons early last season, only to become disenchanted at not being given a starting role.

His departure from Memphis was also believed to have centred on his role on the Grizzlies team and NBA Hall of Famer Barkley believes that if Iverson does find a new team rather than stay retired, he has to be realistic about his future playing role.

"If Allen Iverson wants to play he's not going to be the focal point of a team," Barkley told ESPN Radio on Friday.

"He's probably more than likely going to have to come off the bench and if he can not accept that, he's not going to play.

"There comes a point when you're not the man any more. You have to accept that. It ain't right, it ain't wrong, it's just how it is.

"He's got to accept that or he's going to be sitting at home, simple as that. He's going to have to come off the bench and be instant offence."

Barkley, 46, named one of the NBA's 50 Greatest Players by the league in 1996, said Iverson would join him on another, less enviable honour roll.

"Every year during the play-offs, in any sport, they'll show you the lists, all the great players who never won a championship, and he's on that list with me," Barkley said.