After the loss to Tibau, Pellegrino decided to take a hiatus from MMA. He 'stepped away from the sport as a fighter' and didn't renew his contract with the UFC. A few days later, Pellegrino officially announced his retirement from mixed martial arts.
He returned several months later to make his Bellator debut against lightweight tournament finalist Patricky Freire. Freire blasted Pellegrino in under a minute with a first-round TKO. The New Jersey crowd chanted "Bullshit."
Pellegrino retired after the bout -- briefly.
Pellegrino was next set to compete in Bellator against Marcin Held but he was injured and forced to pull out of the bout.
After recovering Pellegrino was next set to face Saul Almeida. The fight didn't materialize and in January 2014 after his student George Sullivan won a close UFC debut, Pellegrino allowed himself to admit that he was retiring for good.
- Kurt Pellegrino vs. Mac Danzig - The fight was Pellegrino's mixed martial arts debut and Mac Danzig's first loss. Apparently both fighters had fought before in a non-sanctioned/amateur bout and Pellegrino had originally won via TKO. The win was soon turned over to a no-contest because of an alleged headbutt. This was the rematch.
- Satoru Kitaoka vs. Kurt Pellegrino - The fight was the first loss of Pellegrino.
- Kurt Pellegrino vs. Junior Assuncao - The fight was Pellegrino's lightweight debut and his first UFC win.
- Kurt Pellegrino vs. Nate Mohr - The fight was Nate Mohr's UFC debut.
- Kurt Pellegrino vs. Alberto Crane - After the fight, Alberto Crane was cut. Pellegrino had a tooth knocked out within the first seconds of the fight, which ripped a hole in his mouth under his lip.
- Nate Diaz vs. Kurt Pellegrino
- Kurt Pellegrino vs. Thiago Tavares
- Kurt Pellegrino vs. Rob Emerson
- Kurt Pellegrino vs. Fabricio Camoes
- George Sotiropoulos vs. Kurt Pellegrino
- Gleison Tibau vs. Kurt Pellegrino - After the fight, Kurt Pellegrino retired from mixed martial arts.
- Patricky Freire vs. Kurt Pellegrino - The fight was the Bellator debut of Pellegrino. Pellegrino retired afterwards.