BOSTON, MA - JANUARY 06: Aron Baynes #12 of the Detroit Pistons defends Amir Johnson #90 of the Boston Celtics as Isaiah Thomas #4 of the Boston Celtics drives towards the basket during the fourth quarter at TD Garden on January 6, 2016 in Boston, Massachusetts. The Pistons defeat the Celtics 99-94. NOTE TO USER: User expressly acknowledges and agrees that, by downloading and/or using this photograph, user is consenting to the terms and conditions of the Getty Images License Agreement. (Photo by Maddie Meyer/Getty Images)

Cleveland's biggest challenger in the East just added a former NBA champion to its roster

He's a nice addition.

The Boston Celtics have been stockpiling talent this entire offseason after getting Gordon Hayward to sign on the dotted line, drafting forward Jayson Tatum with the third overall pick and trading away Avery Bradley to get depth in the front court with Marcus Morris. Now the Celtics are dipping into the Piston pool again with their latest signing:

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Baynes was with the Pistons last season and the one before. Before that he was with the San Antonio Spurs and won a title with them in 2014. The 6'10" big man should help shore up any rebounding issues the Celtics had before and he's got winning experience to bolster the bench as well. He averaged 4.9 points and 4.4 rebounds in 75 games with the Pistons last season.