Johnny made his first appearance in World Wrestling Entertainment (WWE) when he teamed with Nova in a dark match loss to Chuck Palumbo and Nunzio on the February 23, 2003 episode of Velocity. His pay-per-view debut was at the 2003 Vengeance event, when he appeared as the masked Conquistador Dos in the APA's Barroom Brawl match.
On January 23, 2006, Johnny made his WWE television debut as part of a group of male cheerleaders dubbed The Spirit Squad, appearing on Raw and helping Jonathan Coachman win a Royal Rumble qualifying match against Jerry Lawler by distracting Lawler and performing cheers for Coachman. They later became a part of the ongoing feud between WWE chairman Vince McMahon and Shawn Michaels. The heel McMahon brought in The Spirit Squad to attack Michaels on numerous occasions, including placing them in multiple handicap matches.
They also wrestled in the tag team division and on Raw on April 3, The Spirit Squad won the World Tag Team Championship when Kenny and Mikey, with outside help from the other three members, defeated Kane and The Big Show. After winning the championship, all five members of The Spirit Squad were recognized as the champions, allowing any combination of them to defend the championship.
In May, McMahon signed another handicap match, with The Spirit Squad facing Michaels. The Spirit Squad instead attacked Michaels before the match started, and Triple H came out to help The Spirit Squad. Triple H felt disrespected by The Spirit Squad however, and as a result, helped Michaels instead. This led to Triple H and Michaels reforming D-Generation X (DX) and they began a feud with The Spirit Squad. DX played various sophomoric jokes on The Spirit Squad and the McMahons, as well as defeating The Spirit Squad in handicap tag team matches at Vengeance and a clean sweep in an elimination handicap match at Saturday Night's Main Event XXXIII.
At the same time as their feud with DX and their alignment with McMahon, The Spirit Squad also wrestled other teams in Raw's tag division over their World Tag Team Championship, successfully defending the championship against the teams of Jim Duggan and Eugene, Charlie Haas and Viscera, and Snitsky and Val Venis. They then entered a lengthy feud with The Highlanders, whom they eventually defeated to retain the championship at the Unforgiven pay-per-view in September. The Spirit Squad as a whole later began a losing streak with Johnny, Mikey, and Mitch losing singles matches to Ric Flair on consecutive episodes of Raw. After two consecutive losses to the debuting Cryme Tyme, Kenny announced that he was going to defeat Flair, and was successful with the help of the other members. It was then announced that Flair and a legend, selected by interactive voting, would wrestle the team for the World Tag Team Championship at the Cyber Sunday pay-per-view in early November. The fans chose Roddy Piper, and he and Flair defeated Kenny and Mikey to win the championship.
The group disbanded on the November 27 episode of Raw, when they were defeated in a five-on-three handicap match by DX and Flair. In a backstage segment later that night, DX placed all members into a crate.
Following the breakup of The Spirit Squad, Johnny became the second member of the team to return to the main roster when he appeared during a 30-man battle royal on the December 18 episode of Raw, wearing new wrestling attire. This would be his last appearance in the WWE, however.