In 1994 he entered the K-1 Grand Prix '94 where he caused one of the biggest upsets in K-1 history by flooring three times and subsequently knocking out legendary karateka and future K-1 star Andy Hug with an uppercut after just 19 seconds of the first round in their quarterfinal match.

Some pundits, most notoriously Dave Meltzer, have expressed their belief that Hug's loss was a fight fixed in order to increase Smith's popularity.

Despite his loss, Smith's performance got him invited to UFC 2, now a 16-man tournament, where he entered with the expressed intent of a shot at the previous winner Royce Gracie.

Smith had spent the time between shows working on his grappling to perform better on the ground,[8] which paid off with a victory by guillotine choke against Ray Wizard in the first round.

He opened the fight in spectacular fashion by landing a running front kick to Moncayo's chest, knocking him down and sending him sliding towards the fence.

[10] Smith then followed with a takedown and gained mount position, and ultimately locked a rear naked choke when Moncayo tried to escape, making him tap out.

In an elimination tournament of eight fighters at WVC 5 held in Recife, Brazil on 3 February 1998, Smith withdrew ahead of his scheduled semifinal bout against Igor Vovchanchyn after he suffered a broken hand in his quarterfinal win over Marco Selva.

[13] On April 11, 2008, Smith came in as a late replacement for Gary Goodridge and defeated Eric "Butterbean" Esch via submission due to strikes in a "Masters Superfight" at YAMMA Pit Fighting's inaugural event.