Career
Underhill made his debut for Gloucester at 17 in the LV cup and subsequently in the Aviva Premiership aged 18 years He joined the Ospreys regional team and Bridgend Ravens in 2015 having previously played for Longlevens Rugby Football Club, Sir Thomas Rich"s Grammar School, the Gloucester academy, Gloucester United Reconstruction Finance Corporation, and Gloucester Rugby. He made his debut for Ospreys in the Guinness Pro12 against Ulster and was man of the match in his first start against Munster.