As a native of New York, Matthews wrestled in many promotions around New York City and New Jersey early in his career. In 2004 he wrestled for World Xtreme Wrestling in Pennsylvania teaming up with Greg Matthews. He was managed by Krissy Vaine. On June 14, 2005, Matthews wrestled as enhancement talent in his only appearance in WWE. He teamed with Nick Berk, losing to MNM. He also wrestled in Women Superstars Uncensored from 2006-2010. On December 12, 2009 Matthews lost to Tito Santana at NWS/WSU The Awesome Challenge in Flemington, New Jersey. Matthews spent most of his career performing for Pro Wrestling Syndicate. On May 8, 2010 Matthews defeated boxing legend Butterbean for the PWS Heavyweight Title. The title was vacated on August 20, 2010. He would regain the title by defeating Sami Callihan on June 2, 2012. On November 20, 2012 Matthews dropped the title to Matt Hardy. He would win the title back by defeating Hardy on February 9, 2013. During his reign he defeated Colt Cabana, Anthony Nese, and Homicide. He would drop the title to Alex Reynolds on September 20, 2013. On May 17, 2014 he defeated Jeff Jarrett.
Impact Wrestling (2017–2019)
On March 6, 2017, it was reported that McDonald had signed with Impact Wrestling. On the March 30, episode of Impact Wrestling, he debuted as Sienna'scousin, defeating Braxton Sutter with interference from Sienna. On the May 25, episode of Impact Wrestling, KM teamed with Kongo Kong defeating Braxton Sutter and Mahabali Shera, after both teams began a feud with each other. On June 15, episode of Impact Wrestling that occurred in Mumbai, India, KM competed in a Gauntlet match for the inaugural Sony SIX Invitational Trophy, which was won by Mahabali Shera after he was eliminated by Shera. On July 2, during the Pre Show of Slammiversary XV, KM teamed with Kongo Kong and Laurel Van Ness losing to Mahabali Shera, Braxton Sutter and Allie in a six-person tag team match. On the January 18, 2018 Impact Wrestling tapings, KM attacked James Storm with a beer bottle, smashing it over his head, after he joined the American Top Team. KM then later formed an alliance with Fallah Bahh turning face in the process. In March 2019, his profile was moved to the alumni section of the Impact roster page on their website. Subsequently he stopped appearing on Impact Wrestling's weekly program. Matthews would later argue with Impact owner Scott D'Amore on Twitter over the amount they pay their talent.
