In Ohio Valley Wrestling (OVW), he formed a successful tag team with Rob Conway, called The Lords of The Ring.

[1] While still in OVW, Dinsmore also made some appearances as a jobber in the World Wrestling Federation (WWF), first on an episode of Shotgun Saturday Night in 1999.

WWE wrote Eugene as the "special" and overly excited nephew of Raw General Manager Eric Bischoff, who had savant-like wrestling ability from watching his favorites on television, Dinsmore has described his portrayal of Eugene as being inspired by Rip Rogers' autistic child and Dustin Hoffman's performance in the film Rain Man.

[11] Two weeks later on the August 30 episode of Raw, they fought a no disqualification match, which Eugene won after interference from Randy Orton.

[12] The next week, they had a steel cage match, which Eugene lost and suffered a kayfabe dislocated shoulder, ending the feud.

[15] Eugene suffered an injury at New Year's Revolution on January 9, 2005, in a match with Christian and Tyson Tomko, after botching a dropkick.

[16] During recovery, Eugene made a surprise appearance at WrestleMania 21 on April 3, delivering a promo until being interrupted and attacked by Muhammad Hassan and Daivari.

[1] At Taboo Tuesday on November 1, Rob Conway teamed with Tyson Tomko to face Eugene and a "WWE Legend", to be chosen by the fans.

[20] On November 18, WWE.com reported Dinsmore was rushed to the hospital the previous night, after passing out in a hotel lobby in Manchester, and was suspended indefinitely.

[23] On the September 4 Raw, Eugene and Duggan challenged World Tag Team Champions the Spirit Squad for the title, but were unsuccessful.

On the March 19, 2007, episode of Raw, Eugene was forced into a match with Umaga, as a punishment for accidentally spilling a drink on Vince McMahon.

The following week, he was tricked into thinking Deuce 'n Domino were helping him win his match against Mark Henry, which led to a quick defeat.

On the July 20 episode of SmackDown!, Eugene participated in a battle royal for the vacant World Heavyweight Championship, and was eliminated by Batista and Kane.

Dinsmore made his Ring of Honor debut on December 9, 2010, at ROH Wrestling tapings, losing to Mike Bennett.

[4][36] On July 27, Dinsmore, as "U-Gene", unsuccessfully challenged Freight Train for the 5 Dollar Wrestling championship in the main event of that promotion's internet PPV debut.

[37] On February 20, 2008, Dinsmore returned to Ohio Valley Wrestling (OVW) under his real name and defeated Jay Bradley to win his ninth Heavyweight Championship.

On October 26, 2011, Dinsmore defeated Jason Wayne to win the OVW Heavyweight Championship for the tenth time, turning heel in the process.

[38] Dinsmore lost the title to Rudy Switchblade seven days later in an Eight Man Melee, including Wayne, Adam Revolver, Ted McNaler, James Thomas, Rocco Bellagio and Mike Mondo.

On the August 10 Raw, Eugene returned to television, losing a Contract on a Pole match to The Calgary Kid, who afterwards removed his mask to reveal himself as The Miz.

[44] Dinsmore began running his own shows in Sioux Falls, South Dakota, under the banner of Midwest All Pro Wrestling.

[46] During his run with WWE, Dinsmore's character was "Eugene", an overly-excited and "special" person who could outwrestle anyone in the ring, based upon some people with intellectual disability.