Early career 2011 After compiling an amateur record of 2–0, Emmett started his professional MMA career on October 8, 2011, and made his debut in Capitol Fighting Championship as a
Featherweight. He broke his hand in the first round and continued with the fight and managed to earn his first win by unanimous decision. Emmett had surgery on his broken hand and had a 10 month lay off from competing. He returned to training to prepare for his next fight and broke the same hand on his last sparring session prior to the fight event which forced him to take another long break before returning to the cage.
2013 After his first professional win, he made a move to compete in West Coast Fighting Championship (WFC) and made his debut on August 3, 2013, against Mike Ryan, winning via guillotine choke in the first round. Emmett faced Brandon Ricetti on November 15, 2014, at West Coast Fighting Championship 12 in a five-round fight for the lightweight title belt. In the fifth round, Emmett loaded with punches, pressing Recetti to fall forward when Emmett hit Ricetti with a knee and Ricetti was KO. The fight was ruled a No Decision at first as Ricetti was grounded when he got kneed. However, the decision was overturned after a review of the incident and a win was awarded to Emmett via unanimous technical decision. Emmett was crowned WFC Lightweight Champion.
2015 After he secured the championship belt, Emmett didn't return to compete until almost one year later on October 3, 2015, at
KOTC promotion, facing Rocky Johnson. Emmett showed off his submission skills and won the fight via arm-triangle choke.
2016 Emmett returned to fight in West Coast Fighting Championship promotion in Sacramento, California, US, on January 23, 2016, against
Christos Giagos, a former UFC fighter. Emmett secured a win via TKO at 2:21 of round 3 and also won the ISCF - International Sport Combat Federation (ISCF) Pro California Lightweight Title.
Ultimate Fighting Championship After garnering a 9–0 record as a professional, Emmett signed with the UFC.
2016 Emmett made his promotional debut as a short notice replacement on May 8, 2016, against
Jon Tuck at
UFC Fight Night 87, where he replaced an injured
Nick Hein. Emmett suffered a compound fracture on his left right finger from catching Tuck's spinning back kick and the referee halted the fight briefly prior to restarting. Emmett secured a win with split decision (29-28, 28-29, 29-28). Emmett was expected to face
Jeremy Kennedy on August 27, 2016, at
UFC on Fox 21. However, Emmett was forced out of the event, due to an injury. On December 17, 2016, Emmett faced
Scott Holtzman at
UFC on Fox 22. The three round fight was a back and forth battle and judges awarded the win to Emmett via unanimous decision.
2017 Emmett faced promotional newcomer
Desmond Green on April 8, 2017, at
UFC 210. Emmett was outpointed by Green's striking and lost the fight via split decision of 29-28, 28-29, and 30-27. Emmett faced
Felipe Arantes in a featherweight bout on October 21, 2017, at
UFC Fight Night 118. He won the fight via unanimous decision. Emmett dedicated this win to his friend's son, who has heart condition, at the age of 11 and has gone through an experimental surgery. Emmett faced
Ricardo Lamas on December 16, 2017, at
UFC on Fox: Lawler vs. dos Anjos. At the weigh ins, Emmett weighed in at 148.5 pounds, 2.5 pounds over the featherweight upper limit of 146 pounds and the bout proceeded at a catchweight. Emmett forfeited 30% of his purse to Lamas. Emmett won the fight via knockout in the first round.
2018 Emmett faced
Jeremy Stephens at
UFC on Fox 28, which took place on February 24, 2018, in
Orlando, Florida. Despite hurting Stephens in the first round, Emmett lost the fight by knockout in the second round, after being hurt with a knee and elbows to the head. As a result, Emmett was sidelined for the remainder of 2018, after undergoing successful surgery to correct facial injuries sustained during the Stephens fight.
2019 Emmett faced
Michael Johnson on March 30, 2019, at
UFC on ESPN 2. He won the fight via knockout in the third round. Emmett faced
Mirsad Bektić on July 13, 2019, at
UFC Fight Night 155. He won the fight via technical knockout in round one. This win earned him the
Performance of the Night award.
2020 Emmett was expected to face
Arnold Allen on January 25, 2020, at
UFC Fight Night 166. However, Emmett pulled out the fight, citing an undisclosed injury, and he was replaced by
Nik Lentz. Emmett was expected to face
Edson Barboza on May 2, 2020, at
UFC Fight Night: Hermansson vs. Weidman. However, on April 9,
Dana White, the president of UFC announced, that this event was postponed, and the bout cancelled. With one fight left on his contract, Emmett signed a new four-fight contract with the UFC. He won the bout via unanimous decision. This win earned him the
Fight of the Night award. Emmett was sidelined for the remainder of 2020 and most of 2021, recovering from a litany of injuries to his left leg sustained in the fight, including an
ACL tear.
2021 Emmett faced
Dan Ige on December 11, 2021, at
UFC 269. He won the fight by unanimous decision.
2022 Emmett faced
Calvin Kattar on June 18, 2022, in the main event at
UFC on ESPN 37. He won the close bout via split decision. 14 of the 19 media members scored the fight in favor of Kattar. The bout earned Emmett the
Fight of the Night award.
2023 Emmett faced
Yair Rodríguez for the
Interim UFC Featherweight Championship on February 12, 2023, at
UFC 284. Emmett lost the bout via triangle choke submission in the second round. Emmett was initially scheduled to face
Ilia Topuria on June 17, 2023, at
UFC on ESPN 47. However, the promotion later announced, that the bout was shifted to headline
UFC on ABC: Emmett vs. Topuria on June 24, 2023. Emmett lost the fight via unanimous decision. The bout earned him the
Fight of the Night award. Emmett was scheduled to face
Giga Chikadze on December 16, 2023, at
UFC 296. However, Chikadze withdrew, due to an undisclosed injury, and he was replaced by
Bryce Mitchell. Emmett won the fight via knockout in the first round. This fight earned Emmett the
Performance of the Night award.
2025 Emmett faced
Lerone Murphy on April 5, 2025 in the main event at
UFC on ESPN 65. He lost the fight by unanimous decision. Emmett faced
Youssef Zalal on October 4, 2025 at
UFC 320. He lost the fight via an armbar submission in the first round.
2026 Emmett faced
Kevin Vallejos in the main event on March 14, 2026, at
UFC Fight Night 269. He lost the fight by technical knockout in the first round. ==Championships and accomplishments==