The Boston Celtics' new Big Three will stay together to try for a second NBA title.

Ray Allen confirmed on Wednesday night he has agreed to a two-year, $20 million contract to return to Boston. With Kevin Garnett under contract, Paul Pierce on the verge of a new four-year deal and coach Doc Rivers also agreeing to return, the Celtics can keep together the core of the 2008 NBA champions for at least two more years.

Allen's agent, Lon Babby, said the second year is a player option. NBA teams are not allowed to sign free agents until Thursday.

Allen, who turns 35 this month, averaged 16.3 points last season as the Celtics reached the NBA Finals for the second time in three years. After Boston lost to the Los Angeles Lakers in seven games, Allen said, "It's obvious I don't want to be anywhere else."