Yahoo! Sports is reporting that the Boston Celtics have agreed in principle on a five-year, $55-million contract extension for point guard Rajon Rondo.

Rondo's agent, Bill Duffy, told the web site's Marc J. Spears that he called Celtics GM Danny Ainge yesterday -- as a deadline approached for the two sides to reach an agreement on an extension -- to say that Rondo was prepared to play out his contract and become a restricted free agent next season. Duffy said he was surprised when Ainge said that the Celtics were prepared to meet Rondo's contract wishes.

The $11 million per year that is stipulated in the contract is the same annual amount earned by Spurs star Tony Parker, Spears reports, and puts the 23-year-old Rondo among the league's top-paid players at the position.