Career
Jason is the older brother of Ultimate Fighting Championship veteran Clay Guida. Guida appeared on The Ultimate Fighter: Team Nogueira versus Team Mir and was eliminated in the first episode for failing to make the 206 lb weight limit by one pound.
Following this, as a last minute replacement for Ken Shamrock, Guida faced former WWE pro wrestling star Bobby Lashley.
Guida lost via unanimous decision. Before his bout with Lashley, he and Guida got in a scuffle at a pre-fight press conference that had to be broken up by Roy Jones Junior.
In 2009 Jason was set to take on 2011 ADCC World Championship Nottingham Gold Medalist and current UFC fighter, Vinny Magalhães in the main event of "Carolina Crown 2" as a late replacement for Lance Evans, the brother of UFC star Rashad Evans. He later dropped out of the fight due to a lower back injury sustained during training, he was replaced by Bellator fighter Chris Davis.
In 2010, Guida then tried out for The Ultimate Fighter 12 in the Light Heavyweight division but was unsuccessful when the Light Heavyweights were cut before the season started in favor of a Lightweight only season.
Guida stepped in as a replacement and fought Justin Lemke at Bellator 29 in a 210 lb catchweight bout and his Bellator debut. Guida weighed in 5 lbs over the catchweight limit and the fight was changed to a 215 lb catchweight bout. On November 16, 2012 Guida was scheduled to make his return against former UFC veteran Jason Brilz in the main event of Disorderly Conduct 13.
The fight was later scrapped due to an injury Jason suffered training with Greg Jackson"s Mobile Marketing Association . He lost via unanimous decision.