NBA: Celtics acquire Xavier Tillman from Grizzlies

 Xavier Tillman (2) is headed to the Boston Celtics from the Memphis Grizzlies. (AP Photo/Nikki Boertman)

BOSTON— The NBA-leading Boston Celtics added some depth at center on Wednesday, acquiring big man Xavier Tillman from the Grizzlies in exchange for forward Lamar Stevens and two future second-round draft picks.

With the deal Boston adds some depth in the frontcourt behind 7-footer Kristaps Porzingis, who has struggled with durability, and 37-year-old veteran Al Horford.

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The 6-foot-8 Tillman has appeared in 34 games for Memphis this season, averaging six points, 4.6 rebounds and a career-best 1.7 assists while shooting 40.8% from the field. The fourth-year player is also averaging a career-high one block and 1.2 steals per game, making him one of only 14 players in the NBA averaging a block and steal per game.

Stevens logged 19 games for Boston this season and averaged 2.8 points and 1.6 rebounds in 6.4 minutes per game.

The Celtics entered Wednesday with a 38-12 record.