[8] He soon became a regular in the side after an injury suffered to teammate Gary Sawyer at the beginning of the 2016–17 season.
On 30 January 2017, Purrington completed a move to Championship side Rotherham United for a reported £300,000 fee, signing a three-and-a-half-year contract.
[10] Purrington joined League One club AFC Wimbledon on 1 August 2018 on loan for the 2018–19 season.
[11] He scored his first goal for Wimbledon in an FA Cup tie against Halifax Town on 1 December 2018.
[13] On the same day as his recall, Purrington joined League One club Charlton Athletic on loan until the end of the season.