Trevor Wittman


Trevor Wittman is an American boxing and MMA trainer.

Training career

Compelled to retire from boxing after being diagnosed with a hyperinflated lung, Wittman transitioned to training boxers in the Denver metropolitan area. He founded T's K.O. Fight Club in Wheat Ridge, Colorado in March 1998. The business broadened its scope to include other combat sports such as mixed martial arts, eventually resulting in Wittman closing T's K.O. Fight Club and establishing the Grudge Training Center facility in Wheat Ridge in 2009. Grudge relocated to Arvada, Colorado in 2013. Having developed experience working with and making training equipment for fighters, in 2015 Wittman founded ONX Sports, a combat sports equipment company. To focus more attention on ONX Sports, Wittman closed down Grudge in November 2016, though he continues to train a few select fighters, including Rose Namajunas, Justin Gaethje, and Matthew Lopez.

Personal life

Wittman wrestled at Berlin High School, after which he moved to New Jersey, then to Colorado, where he attended the Colorado Institute of Art. Wittman married wife Christina in 2005, and has a son Terrence and a daughter Marissa.

Notable MMA fighters trained

2017 Shawn Tompkins Coach of the Year award.