removed from the card the following day after the promotion deemed that a suitable opponent could not be arranged on short notice. Rothwell next faced Josh Barnett on January 30, 2016, at UFC on Fox 18. He won the fight in the second round due to a guillotine choke, making Rothwell the only fighter to ever stop Barnett with a submission hold during Barnett's lengthy MMA career. The win also earned Rothwell his second Performance of the Night bonus award. Rothwell faced Junior dos Santos on April 10, 2016, at UFC Fight Night 86. He lost the fight via unanimous decision. Rothwell was expected to face Fabrício Werdum on September 10, 2016, at UFC 203. However, Rothwell pulled out of the fight on August 11 citing a knee injury and was replaced by Travis Browne. The bout with Werdum was rescheduled and expected to take place on May 13, 2017, at UFC 211. However, the bout was canceled due to Rothwell failing a drug test. On April 6, 2018, it was announced Rothwell had accepted a two-year suspension from USADA, retroactive to February 6, 2017. Having served his suspension, Rothwell returned to face Blagoy Ivanov on March 9, 2019, at UFC Fight Night 146. He lost the fight by unanimous decision. A rematch with Andrei Arlovski took place on July 20, 2019, at UFC on ESPN 4. He lost the fight via unanimous decision. Rothwell faced Stefan Struve on December 7, 2019, at UFC on ESPN 7. He won the fight via technical knockout in round two. The finish was controversial as Rothwell had accidentally hit Struve in the groin twice and was docked one point for these infractions in the second round. The referee encouraged the compromised Struve to continue, resulting in a finish for Rothwell late in the second round. Rothwell was scheduled to face Gian Villante on April 18, 2020, at UFC 249. However, the event and Rothwell's scheduled bout against Villante was cancelled due to the COVID-19 pandemic. Rothwell faced Ovince Saint Preux at UFC Fight Night: Smith vs. Teixeira on May 13, 2020. He won the fight via split decision. Rothwell faced Marcin Tybura on October 11, 2020 at UFC Fight Night 179. He lost the fight via unanimous decision. Rothwell was scheduled to face Philipe Lins on March 13, 2021, at UFC Fight Night 187. However, during the week leading up to the event