While studying in Cortland, Sterling was invited by Jones to try out mixed martial arts at his gym of that time, The BombSquad in
Ithaca, New York. Sterling started his professional career 2–0, before earning a shot at the ROC Bantamweight Championship. He would go on to defeat
Claudio Ledesma by split decision to capture the title. Although this would turn out to be his last bout under the Ring of Combat organization, as he would later sign with
Cage Fury Fighting Championships. Sterling made his CFFC debut in a Featherweight bout against Evan Chmieleski. He won the fight by TKO with just two seconds left in the first round. This victory earned him a shot at the vacant CFFC Bantamweight Championship. Sterling defeated Sean Santella via unanimous decision to capture his second professional title. He would go on to defend the CFFC Bantamweight Championship on three occasions. Sterling finished all three of his title defenses by
rear naked choke, which earned him the opportunity to compete in the
UFC.
Ultimate Fighting Championship 2014 Sterling was scheduled to make his UFC debut at
UFC 170 against
Lucas Martins, replacing an injured
Bryan Caraway. However Martins was eventually injured as well and replaced by fellow UFC newcomer Cody Gibson. Sterling won the fight via unanimous decision. Sterling made his second UFC appearance on July 16, 2014, at
UFC Fight Night 45 against
Hugo Viana. After controlling the majority of the fight Sterling landed a barrage of punches from the mount position causing the referee to wave off the fight late in the third round. Sterling was expected to face
Mitch Gagnon at
UFC Fight Night: MacDonald vs. Saffiedine on October 4, 2014. However, Sterling pulled out of the bout and was replaced by
Rob Font. Following a quick recovery, Sterling was promptly rebooked and was expected to face
Frankie Saenz on November 8, 2014, at
UFC Fight Night 55. However, Saenz was forced to withdraw from the bout and in turn promotional newcomer Michael Imperato was briefly linked as a replacement. However, his signing was quickly rescinded and as a result, Sterling was pulled from the event altogether.
2015 Sterling was expected to face
Manny Gamburyan on April 18, 2015, at
UFC on Fox 15. However, Gamburyan pulled out of the bout citing injury and was replaced by
Takeya Mizugaki. Sterling won the fight by submission in the third round. Sterling faced
Johnny Eduardo on December 10, 2015, at
UFC Fight Night 80. He won the fight via submission in the second round.
2016 Sterling next faced
Bryan Caraway on May 29, 2016, at
UFC Fight Night 88. Despite dominating the first round, Sterling began to tire and would go on to lose the following two rounds and lose via split decision. Sterling was expected to face
Raphael Assunção on December 9, 2016, at
UFC Fight Night 102. However, Sterling pulled out of the fight on November 23 citing injury. Assunção was subsequently removed from the card.
2017 The bout with Assunção was rescheduled and took place on January 28, 2017, at
UFC on Fox 23. Sterling lost the fight via split decision. Sterling faced
Augusto Mendes on April 15, 2017, at
UFC on Fox 24. He won the fight by unanimous decision. Sterling faced
Renan Barão on July 29, 2017, at
UFC 214. The fight was initially contracted to be contested at bantamweight, however on June 28, the
CSAC announced that they would not license Barão to compete at that weight due to his
struggle to make the required weight at
UFC 177. The bout with Sterling proceeded as scheduled at a catchweight of 140 lbs. Sterling won the bout by unanimous decision. Sterling was expected to face
Rani Yahya on December 9, 2017, at
UFC Fight Night 123. However, Yahya pulled out from the event on November 7, 2017, due to injury, and was replaced by
Marlon Moraes. He lost the fight via KO in the first round.
2018 Sterling faced
Brett Johns on April 21, 2018, at
UFC Fight Night 128. He won the fight via unanimous decision. Sterling faced
Cody Stamann on September 8, 2018, at
UFC 228. He won the fight via submission in the second round.
2019 Sterling faced
Jimmie Rivera on February 17, 2019, at
UFC on ESPN 1. He won the fight by unanimous decision. Sterling faced
Pedro Munhoz on June 8, 2019, at
UFC 238. He won the fight by unanimous decision.
2020 Sterling faced
Cory Sandhagen on June 6, 2020, at
UFC 250 in a bout that UFC president Dana White confirmed to be a bantamweight title eliminator. He won the bout via submission in the first round. This win earned him his first
Performance of the Night.
UFC Bantamweight Champion Sterling was expected to face
Petr Yan for the
UFC Bantamweight Championship on December 12, 2020, at
UFC 256. However, on November 22, it was announced the bout was scrapped from the UFC 256 card due to undisclosed reasons and the bout took place on March 6, 2021, at
UFC 259. Sterling won the fight by disqualification due to an intentional illegal knee in the fourth round, becoming the new
UFC Bantamweight Champion. He became the first fighter in UFC history to win a championship by disqualification. A rematch with Yan was expected to take place on October 30, 2021, at
UFC 267. However, on September 25, Sterling withdrew from the contest due to lingering neck issues from surgery. The pair was initially rescheduled to meet at
UFC 272 on March 5, 2022, but the bout was pushed back to
UFC 273 on April 9. Sterling won the close bout and defended the title via split decision. 11 of 18 MMA media outlets scored the bout for Sterling, while 5 scored it as a draw. Sterling successfully defended his title against
T.J. Dillashaw on October 22, 2022, at
UFC 280. Following a shoulder dislocation suffered by Dillashaw in the first, Sterling defended the title via TKO in the second round, marking his first victory by strikes in nearly eight years. Sterling faced
Henry Cejudo on May 6, 2023, at
UFC 288. He won the fight by split decision and retained his title. 21 of 23 MMA media outlets scored the bout for Sterling, while 2 scored it for Cejudo. Sterling faced
Sean O'Malley on August 19, 2023, at
UFC 292. He lost the fight by second-round technical knockout and lost his title.
Move to Featherweight Sterling moved up to the featherweight division and faced
Calvin Kattar on April 13, 2024, at
UFC 300. He won the fight by unanimous decision. On an episode of The MMA Hour following the win, Sterling confessed he would have considered retiring if he lost to Kattar. Sterling was scheduled to face
Movsar Evloev on October 5, 2024 at
UFC 307. However, Sterling withdrew from the fight due to an injury sustained in sparring. The pairing was eventually rescheduled to
UFC 310 on December 7, 2024. Sterling lost the fight by unanimous decision. Sterling faced former
UFC Featherweight Championship challenger
Brian Ortega on August 23, 2025 at
UFC Fight Night 257. Originally slated as a featherweight bout, the fight was changed to a 153-pound
catchweight after reports that Ortega experienced complications during his weight cut. He won the fight via unanimous decision. ==Professional grappling career==