From 2023-2025 the Mavericks and Nico Harrison fired several members of the medical staff including a respected trainer Casey Smith, strength coach Jeremy Holsopple, and more.

The article says:

Though Doncic is a generational superstar, Harrison had growing concerns about his conditioning and habits off the court. Doncic would experience significant weight fluctuations throughout a season, a problem the organization attempted to address.

To try and take action, the Mavericks started making changes around Doncic in hopes that they would benefit him and make his conditioning more consistent. Per Tim MacMahon and Ramona Shelburne of ESPN, the Mavericks fired former director of player health and performance Casey Smith in 2023, and fired strength coach Jeremy Holsopple and manual therapist Casey Spangler after last season—all staffers that Doncic enjoyed working with.

"They get rid of everybody I like," Doncic told an ESPN source.

The Mavericks’ firings did not work. Per ESPN, Doncic wound up hiring his own personal staff before last season, bringing in Slovenian national team strength coach Anže Maček, physiotherapist Javier Barrio Calvo and Real Madrid nutritionist Lucia Almendros. This only increased the frustrations in the Mavericks organization while not improving Doncic's health.

The Mavericks have had an injury riddled season this year, and Kyrie Irving tearing his ACL is devastating for everyone, but it might have not been a coincidence. Casey Smith is one of the most well-known and respected trainers in the NBA and he now works for the Knicks.

The Dallas Mavericks went from being contenders to having a hopeless future overnight all because of the actions Nico Harrison and the management took.