1995, Don Frye helped train Dan Severn for the Ultimate Ultimate 1995, accompanying Severn's entourage to Denver. He soon made the jump to the burgeoning sport of mixed martial arts himself and joined the Ultimate Fighting Championship the following year. Debuting at UFC 8 in Bayamón, Puerto Rico on February 16, 1996, Frye was among the eight competitors in the openweight tournament that night and was one of two fighters of the era skilled in both stand-up and ground fighting, the other being Marco Ruas. In the quarter-finals, he set the record (since broken by Duane Ludwig and Jorge Masvidal) for fastest knockout in UFC history when his punches knocked down 410-lb Thomas Ramirez in just eight seconds. After a quick technical knockout of Sam Adkins in the semis, taking him down and landing hammerfists to the face for the TKO, he met with Gary Goodridge in the final, and forced the Trinidadian to submit simply by gaining dominant position at the 2:14 mark, though not without landing multiple uppercuts standing and punches on the ground. This would be the first in a trilogy of fights between the pair. Due to the controversy surrounding MMA at the time, Frye was barred from both firefighting, his previous occupation in his hometown of Sierra Vista, Arizona, and from training in the Buena High School gym he had used since his ASU days following the event. Frye returned at UFC 9 in Detroit, Michigan on May 19, 1996 for a match with fellow tournament winner Marco Ruas, but Ruas was injured and replaced by Brazilian jiu-jitsu stylist Amaury Bitetti. Frye stopped his opponent's takedowns and land punches, knees and elbows, and used a judo ude-garami on the jiu-jitsu champion, something that was unusual at the time. At the end, after an especially hard series of strikes to the spine and head of the Brazilian, the match was stopped and Frye was declared winner. At UFC 10 in Birmingham, Alabama on July 12, 1996, Frye returned to tournament format. He defeated Mark Hall by stoppage, slamming the Moo Yea Do specialist and working his side with body punches until the stoppage, and then defeated Brian Johnston, again leading the action to the mat and landing elbows to the head. However, at the finals of the event, Frye faced Mark Coleman, who was considered the "godfather" of the ground and pound strategy Frye often followed.