BOSTON (CBS) — Heading into Monday night’s Celtics-Hawks matchup at the TD Garden, Dennis Schroder is still pretty upset at Isaiah Thomas.

The Hawks guard is still miffed about comments he claims Thomas made back on January 13, when Celtics beat the Hawks down in Atlanta. Schroder claims that Thomas had some unkind things to say about — and to — his family, taking things far beyond the “trash talk” rules. He reiterated those claims on Monday morning in Boston.

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Thomas has denied saying anything about Schroder’s family, and is upset that Schroder’s “lies” are in turn an attack on his own character.

“I don’t talk about nobody’s moms. I don’t cuss at nobody’s moms,” Thomas told reporters following Schroder’s initial claims. “And I don’t talk about people’s families. So whatever he said, that’s a 100 percent lie. And he knows that. Because I always say keep it hoop. When it comes to basketball, I talk about basketball. And I’m going to trash talk, and I’m going to compete.

“I’m going to do whatever I can to make my team win a game. But I don’t bring parents in it. I don’t bring family,” he continued. “I don’t even know his mom to curse at her like he said I did, or whatever he’s lying about. From this point on, I don’t even want to talk about Dennis Schroder because he’s not even on the level that I’m trying to be on. And I’m not even focused on him anymore.”

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The beef between the two guards dates back to last season’s playoff series, when Thomas hit Schroder in the head as the Hawks guard ran down the floor after a layup in Game 3. Thomas was not suspended, but was hit with a fine and retroactively assessed a Flagrant-1 for the incident.

That heat has carried over into this season, and will likely be reignited on Monday night in Boston. With Schroder once again bringing up claims of Thomas disrespecting his family, there could be a few more tense moments between the two.

Tune in to Celtics-Hawks on 98.5 The Sports Hub — the flagship station of the Boston Celtics. Pregame coverage with Sean Grande and Cedric Maxwell begins at 7 p.m.!

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