The Dallas Mavericks have made a change to their training staff following the season-ending injury to Dereck Lively II.
According to NBA insider Marc Stein, a postgame dispute broke out between sports performance director Johann Bilsborough and strength coach Keith Belton after Dallas was eliminated by Memphis in the play-in tournament.
The source reports that the conflict stemmed from how Lively’s foot injury was managed.
ESPN’s Tim MacMahon reports that head athletic trainer Dionne Calhoun has also been dismissed.
Lively suffered a stress fracture in his right ankle in January and was sidelined for nearly three months during a critical stretch of the season.
The 21-year-old had emerged as a key piece in the Mavericks’ lineup, averaging 9.1 points, 7.8 rebounds, and 2.6 assists in 32 appearances.
After the internal blowup, Dallas decided to part ways with Belton, who had served on the Mavericks’ staff as a strength and conditioning coach.
Bilsborough is expected to remain with the organization.
This move marks another low point in a disastrous 2024–25 campaign for Dallas, which ended with the franchise missing the playoffs one year after reaching the NBA Finals.
Injuries ravaged the roster throughout the season.
Anthony Davis, acquired in the controversial Luka Doncic trade in February, missed significant time after suffering an adductor injury in his Mavericks debut. Kyrie Irving was also ruled out for the year in March with a torn ACL.
By mid-March, the Mavericks were down to just eight active players — the league’s minimum requirement — due to injuries.
Lively’s extended absence further depleted a rotation already dealing with constant setbacks.
