Nowinski was one of the three finalists on the WWF's first season of Tough Enough in 2001, which Maven Huffman won.
On the June 10, 2002, episode of Raw, Nowinski debuted in WWE as a heel and stayed heel, helping William Regal beat Bradshaw in a European Championship match. Nowinski had a short-lived alliance with Regal, defeating Spike Dudley in his debut match the following week with Regal in his corner. Nowinski teamed with Regal on the June 24 episode of Raw, defeating Bradshaw and Dudley. Nowinski continued to feud with Bradshaw over the next few weeks, with their feud ending on the July 8 episode of Raw, where Nowinski teamed with Jackie Gayda in a losing effort against Bradshaw and Trish Stratus, while also trying to warming up Regal from his breakdown after he lost the European Championship to Jeff Hardy. Nowinski feuded with The Dudley Boyz (Bubba Ray Dudley and Spike Dudley) through the summer.
Nowinski defeated Tommy Dreamer on the September 9 episode of Raw. A week later, Dreamer attacked Nowinski in a classroom. Their feud ended on the October 14 episode of Raw, where Nowinski was once again successful in defeating Dreamer. Over the next few weeks, Nowinski claimed victories over Jeff Hardy and Booker T before starting a feud with his former Tough Enough trainer, Al Snow. After defeating Snow in two consecutive weeks, Maven began to help Snow against Nowinski. On the November 25 episode of Raw, Nowinski went against Maven in a match that ended in a no contest. Nowinski teamed with D'Lo Brown to defeat Snow and Maven on two occasions. Nowinski then continued his feud with Maven into 2003, where Test aligned himself with Maven for a few weeks, successfully defeating Nowinski and Brown on January 13, 2003 episode of Raw.
On the March 31 episode of Raw, Nowinski was defeated by Scott Steiner. The feud come to an end on the May 12 episode of Raw, where Nowinski teamed with La Résistance (Rene Dupree and Sylvain Grenier) in a losing effort against Steiner, Test and Goldust. On the May 26 episode of Raw, Nowinski aligned himself with Thuggin' and Buggin' Enterprises, an African American wrestling stable consisting of Rodney Mack, Jazz and their manager Theodore Long. At Insurrextion, Nowinski teamed with Mack and Long in a losing effort against The Dudley Boyz (Bubba Ray Dudley, D-Von Dudley and Spike Dudley). At Bad Blood, Nowinski and Mack defeated The Dudley Boyz (Bubba Ray and D-Von). Nowinski wrestled his final match with WWE on the June 23 episode of Raw, in a losing effort against Maven. Nowinski retired from wrestling soon thereafter.