June 8, 2018; Cleveland, OH, USA; Cleveland Cavaliers center Kendrick Perkins (21) during the second quarter in game four of the 2018 NBA Finals against the Golden State Warriors at Quicken Loans Arena. The Warriors defeated the Cavaliers 108-85 to complete a four-game sweep. Kyle Terada-USA TODAY Sports

The 2008 Boston Celtics spent a large part of the last decade feuding but the roots of the conflict go way back. Two of the main figures were Ray Allen and Rajon Rondo, who had issues while still teammates in Boston.

How severe were those issues? Former Celtic Kendrick Perkins shed some light on that in an appearance on “The Old Man & The Three” podcast. Perkins claimed that things were so toxic between Rondo and Allen that the rest of the team forced them to box at the practice facility to try to settle things.

“When things started to go south, in my opinion, the first incident was Ray pushing so hard to trade Rondo for (Chris Paul). Then it got back to Rondo, and I think right there we started having a little friction,” Perkins said. “We made Ray and Rondo actually box it out. They had so much beef, we got to the practice facility, we brought the boxing gloves, and they actually had to box it out, because we just didn’t want to have the tension no more.”

Perkins did say that things have gotten better between members of the ex-Celtics, and everyone is back on “talking terms.”

Perkins has told the story about the alleged Paul trade before, but this is the deepest he has gone into how much Allen and Rondo disliked each other. The tension was clear from the outside, but you don't usually hear about two teammates with that much bad blood between them.

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