The highly rated keeper joined the Reds as a 14-year-old and has proved his qualities at Premier League level.
Henderson initially started as an outfield player as a schoolboy at Carlisle United but is now regarded as one of the finest English goalies after two splendid seasons on loan with Sheffield United.
Each of the Cumbrian's temporary transfers have been huge successes, taking a step up on each occasion. This process started in 2016 with Stockport County, only for a dramatic recall from the Hatters when David De Gea was injured and, with Joel Pereira cup tied, Henderson was named on the bench for the FA Cup win at Shrewsbury Town, one of his future destinations.
A switch to Grimsby Town came first in August 2016, and he played seven times for the League Two outfit before getting the loan extend, only to be recalled again due to an injury to Pereira. Henderson was part of the England squad that won the Under-20 World Cup in Slovakia in June 2017 - he was an unused substitute in the final as the young Lions beat Venezuela. He has since gone on to represent his country at Under-21 level and has been drafted into Gareth Southgate's senior squad.
The 2017/18 season was a landmark one for the youngster as he performed magnificently for Shrewsbury, throughout his loan spell, appearing twice at Wembley and earning a place in the PFA Team of the Year for League One. Immensely popular with the Shrews faithful, he helped the team go all the way to the play-off final, only to lose to Rotherham United, despite Henderson's fine individual display.
The first outing at Wembley came in the EFL trophy but, again, it ended in disappointment as Lincoln City won 1-0. Nevertheless, the confident stopper enhanced his reputation considerably and was rewarded with a new contract at United.
However, such is the fierce competition for places in the goalkeeping department at all levels at United, he joined Championship side Sheffield United on loan for the 2018/19 season in search of more regular first-team football, on the back of his impressive stint at Shrewsbury. The move was an outstanding success as he won the Golden Glove award for keeping the most clean sheets in the division and was a key part of the Blades' promotion to the Premier League.
With his stock continuing to rise, he was England's no.1 in the Under-21 European Championship in the summer of 2019.
On 26 July, the club announced that Dean had signed a new long-term contract with the Reds and returned to Sheffield United on another season-long loan, to gain valuable top-flight experience.
Henderson made his Premier League debut in a 1-1 draw at Bournemouth on 10 August and kept his first clean sheet in the competition the following week, when the Blades overcame Crystal Palace at Bramall Lane. One of the side's stand-out performers all season, he was voted their Young Player of the Year and cemented his status as one of the division's most reliable keepers.
On 26 August 2020, he signed a new long-term contract with his boyhood club, committing his future to the Reds until 2025 with the option of a further year.
Henderson made his Reds first-team bow at Luton in the Carabao Cup in September 2020, keeping a clean sheet as Ole Gunnar Solskjaer's side progressed to the fourth round with a 3-0 victory, and followed that up with a first appearance for the senior England side, coming on as a half-time substitute during the Three Lions' 3-0 friendly win over Republic of Ireland on 12 November 2020.