The Boston Celtics and Los Angeles Clippers are close to completing a deal that will release Doc Rivers from the final three years of his contract to take over as the coach of the Clippers, in exchange for an unprotected 2015 first-round pick, a league source told SB Nation.

Rivers has agreed to a three-year, $21 million deal to coach the Clippers, Yahoo! Sports' Adrian Wojnarowski reports.

The league would have to approve the unusual deal before it can be finalized. However, sources believe that the NBA would approve one, but not both, of the rumored deals between the two clubs, meaning that the discussed Kevin Garnett trade for DeAndre Jordan is off the table. It's likely the Celtics will now retain Garnett, who has two years left on his contract, as well as a no-trade clause.

Wojnarowski first reported that talks between the two teams were back on Sunday after the league raised concerns Thursday about the proposed deal involving both Rivers and Garnett.

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