He signed on loan for
Bolton Wanderers in August 2020.
[8] His debut came on 5 September in Bolton's first match of the season, a 1–2 home defeat against
Bradford in the first round of the
EFL Cup.
[9] On 28 September Crellin was defended by Bolton head coach
Ian Evatt after being criticised for perceived errors in games.
[10] A month later however, Evatt criticised Crellin, stating that he needed to "man up" and that Bolton could not afford for their goalkeeper to keep making so many mistakes, after Crellin was at fault for two of
Barrow's goals in a 3–3 draw and four days later scored an own goal in a 1–1 draw against
Cambridge United.
[11] In the next match Crellin saved a
penalty to help Bolton beat
Bradford City 1–0
[12] and was voted
Man of the Match by the Bolton fans.
[13] Evatt praised Crellin for responding to the criticism by putting on the Man of the Match display.
[14] Crellin continued to make mistakes however
[15] and on 13 November he was dropped to the bench for Bolton's derby match against
Salford City.
Erm, Welcome to Everton lad.