Source: Kings to acquire Cassell

The Sacramento Kings agreed in principle to a deal with the Boston Celtics on Monday night, a league source told ESPN.com. The Celtics will send Sam Cassell and cash to the Kings for a future second-round pick.

Barring any changes overnight, the deal is expected to be finalized Tuesday afternoon with the league office.

The deal helps the Celtics by removing Cassell's salary from the team's luxury-tax computations. The Kings give up virtually nothing to do it as the pick is heavily protected. Furthermore, another league source says the deal could pave the way for the Celtics to add another player to their roster prior to the playoffs. The Celtics had a maximum of 15 players on their current roster.

Cassell hasn't played a game for the Celtics this season, but he's been an important veteran voice in the locker room. While it's unclear what the Kings will do with Cassell, most likely they'll waive him.

Chad Ford covers the NBA for ESPN Insider.