The Los Angeles Clippers have reached an agreement in principle to send an unprotected 2015 first-round draft pick to the Boston Celtics for the rights to hire coach Doc Rivers, league sources told Yahoo! Sports.

Rivers has agreed to a three-year, $21 million deal with the Clippers, league sources said.

Talks started again on Sunday when the Clippers offered the Celtics the first-round pick to free Rivers from his contract with Boston, sources said.

The NBA still needs to grant approval to the deal, but the teams have been led to believe that won't be a problem, sources said.

The Clippers and Rivers believe Rivers' arrival will solidify star free agent Chris Paul's commitment to sign a five-year contract extension in July, sources said.

Rivers told the Clippers that he was no longer interested in the position on Friday, but pressure from Paul stayed strong on Clippers management over the weekend and Los Angeles reconsidered its unwillingness to give Boston a first-round pick, sources said.