Date of birth
An international for England at various youth levels, Jackson signed for the Reds in the summer of 2016 from Middlesbrough, penning a three-year deal.
'Jacko' spent the 2015/16 campaign away from the Riverside on loan with Hartlepool where his storming performances were key to the club surviving in League Two and alerted the Reds to his ability.
The 23-year-old defender made 11 appearances for Barnsley during the 2016/17 season as he struggled to force his way into the team owing largely to the performances of others.
However, Jackson fought his way back into the team at the start of the 2017/18 season and was in fine form at the heart of the defence.