Having come through the Sunderland academy ranks, Henderson made his senior debut in 2008 and quickly became a central figure in the midfield. Over three seasons, he accumulated 79 appearances for the club before sealing a high-profile £20 million move to Liverpool just before turning 21.
Now plying his trade in the Eredivisie with Ajax, Henderson endured a bittersweet ending to the 2024–25 season. Despite Ajax’s strong campaign, they missed out on the Dutch league title on the final day, losing out to PSV Eindhoven by just a single point.