Oliver Westfield Claffey is an English professional wrestler and mixed martial artist best known for his work with WWE as Gentleman Jack Gallagher.
In 2007, Claffey began training and working as a professional wrestler. He wrestled for several English and American promotions and won multiple championships before signing with WWE.
In 2016, Claffey signed with WWE and entered the CWC. During the tournament, Akira Tozawa eliminated him. After the event, he joined the 205 Live roster. In 2017, he made an appearance in the Royal Rumble match and was eliminated by Mark Henry.
At Fastlane, Gallagher faced Neville for the WWE Cruiserweight Championship and lost. In April, he went to NXT UK and challenged Tyler Bate in a losing effort. In September, Gallagher turned heel on Cedric Alexander. Gallagher spent the next two years in the cruiserweight division. In 2020, they released him from the company.