Palomino began his career with a 3–0 record in the Absolute Fighting Championship promotion, one of which being a victory over future The Ultimate Fighter 7 competitor Jeremy May via unanimous decision.
In his final fight prior to joining Bellator, Palomino fought John Mahlow for the XFC Lightweight Championship, in a bout that was featured on the Inside MMA show.[5] Palomino lost the fight via a rear-naked choke submission in the fifth round.
Despite his elimination from the featherweight tournament, Palomino stayed with the Bellator promotion and continued in the featherweight division.[8] His opponent at Bellator 6 was Nick Gonzalez and Palomino defeated him via TKO (punches) in the second minute of the first round.[9]
Palomino next faced Troy Gerhart at Bellator 12 in a 150lb bout[10] and defeated him via unanimous decision (29–28, 29–28, 29–28).[11]
After the first season of Bellator ended, Palomino took a few fights outside of the promotion. Palomino lost his first fight to eventual The Ultimate Fighter winner Jonathan Brookins via submission (rear naked choke) in the second round. Palomino followed the loss up with two victories including wins over Rafael Dias by TKO and Jorge Masvidal via split decision.
In his next Bellator appearance at Bellator 21, Palomino defeated Jose Figueroa via unanimous decision in a lightweight bout.[12]
Palomino then stayed with Bellator into the third season. His first fight of the season was against Yves Edwards at Bellator 24,[13] which he lost via unanimous decision.[14]
Championship Fighting Alliance
Palomino signed with local promotion Championship Fighting Alliance, Palomino quickly made his CFA debut on May 6, 2012 in Miami, Florida against Peter Grimes for the inaugural CFA Featherweight championship at CFA's inaugural event; CFA: The Title. Palomino defeated Grimes by submission due to an armbar at 4:59 of round 4.
Palomino returned at CFA 04: Izquierdo vs. Cenoble on December 17, 2011 in Coral Gables, Florida against well known journeyman Charles Bennett. Palomino was able to use his speed advantage to counter punch the aggressive Bennett and ultimately knocked Bennett out at 3:59 of the first round. Palomino became only the second man to knock Bennet out.
Palomino was scheduled to fight former Maximum Fighting Championship Lightweight ChampionAntonio McKee at CFA 06 on 13 April 2012 in Coral Gables, Florida. McKee was forced off the card due to an injury and was replaced by James Warfield, the fight was originally scheduled for the CFA Lightweight Championship but Warfield did not make the required weight of 155 pounds thus rescheduling the fight to a non-title bout. Warfield knocked Palomino down in the first round but Palomino was able to recover and control the rest of his fight by using his unorthodox and fast striking to pick Warfield thus winning by unanimous decision.
Palomino next faced 2x Hero's Grand Prix winner and Strikeforce veteran Gesias Cavalcante at CFA 07: Never Give Up on 30 June 2012 in Coral Gables, Florida. Palomino became the first man to ever finish Cavalcante and he did so via third-round knockout due to punches.
Palomino returned to action at CFA 09 on 19 January 2013 when he faced PRIDE veteran Luiz Firmino for the CFA Lightweight Championship, Palomino lost a unanimous decision after being constantly outgrappled and taken down throughout the fight.
Palomino bounced back from his previous defeat on 24 May 2013 at CFA 11 by knocking out Robert Washington in the first round.
Palomino faced Gaethje in a rematch on September 18, 2015 at WSOF 23. It was again a back-and-forth battle that Palomino lost via TKO in the second round.
Palomino next entered WSOF's one night Lightweight tournament to determine the number one contender for the Lightweight Championship.[17] He faced Rich Patishnock in the quarter-finals and won via knockout in the first round. He then faced Brian Foster in the semifinals and lost via TKO in the second round.[18]
Absolute Championship Berkut
Palomino faced Chechen fighter Musa Khamanaev on January 13, 2017 at ACB 51.[19] He won the fight via TKO in the second round.
In the second fight he faced Marcos Vinicius Schmitz on May 20, 2017 at ACB 61. He won the fight via unanimous decision.
Palomino faced Yusuf Raisov on August 19, 2017 at ACB 67. He lost the fight via unanimous decision.
Bare-knuckle boxing
After signing a three-fight contract with the BKFC, Palomino made his debut in bare-knuckle boxing against Elvin Brito at BKFC 10 on February 15, 2020. Palomino won the fight via unanimous decision and advanced to the four-man BKFC Super Welterweight Tournament finals.[20] This fight earned him the Fight of the Night award.[21]
Palomino was initially scheduled to face Jim Alers at BKFC 11 on March 14, 2020 for the Lightweight Championship, but the event was postponed to take place on June 20, 2020 due to the COVID-19 pandemic.[22] The event was subsequently postponed yet again and two weeks before the rescheduled date July 24, 2020, Alers withdrew after his camp member tested positive for COVID-19 and was replaced by Isaac Vallie-Flagg.[23] Palomino claimed the title via first-minute knockout.[24]
The bout with Alers was then rebooked to take place at BKFC 14 on November 13, 2020. Palomino successfully defended his championship via first-minute knockout.[25]
In his second title defense attempt, Palomino faced Tyler Goodjohn at BKFC 18 on June 26, 2021. Palomino retained his title and won the bout via unanimous decision.[26]
He next faced Dat Nguyen at BKFC 22 on November 12, 2021.[27] He successfully defended the title via unanimous decision.[28] This fight earned him the Fight of the Night award.[29]
He successfully defended his title by defeating Martin Brown at BKFC: KnuckleMania 2 on February 19, 2022 via unanimous decision.
Following his routing of Brown, Palomino set his sights on becoming the first two-division champion in the BKFC. He faced off against welterweight champion Elvin Brito at BKFC 26 on June 24, 2022. He won by the welterweight championship by unanimous decision. In a January 2024 interview, Palomino said he was stripped of the welterweight belt.[30]
Palomino faced James Lilley and defended his lightweight title on June 23, 2023 at BKFC 45: Hollywood and won by unanimous decision.[31]
In a January 2024 interview, Palomino said he was no longer fighting in the lightweight division and would vacate the belt because there was no money or big fights in the division.[30]
On February 2, 2024 at BKFC 57 in Hollywood, Florida, Palomino fought Austin Trout for the vacant BKFC welterweight title and lost his first bare-knuckle boxing bout by unanimous decision.[32]
Boxing
Palomino is scheduled to make his pro boxing debut against Gabriel Rosado on November 12, 2024 in Miami.[33]
