The Celtics lost one of their key reserves in free agency as Luke Kornet is headed to the Spurs. Kornet agreed to a four-year, $41 million deal with San Antonio, a source confirmed to MassLive, as the big man got an expected big contract on the open market. ESPN’s Shams Charania was the first to report the deal.

Free agent center Luke Kornet has agreed to a four-year, $41 million deal with the San Antonio Spurs, sources tell ESPN.

Luke Kornet is leaving Boston after signing a four-year, $41 million contract with the San Antonio Spurs. according to a league source.