Ahead of the 2020–21 season, Nelson made new signings, with a help from the "Impact of the Future Fund" and "the 1899 Club" support groups and praised the groups for their role in helping him bring in new players. However, Blyth Spartans struggled in the league, winning only once in fourteen league matches before the season was ended early because of the COVID-19 pandemic for the second time. During the 2020–21 season, he once came out of retirement as a replacement for the suspended Matthew Elsdon and played in the FA Cup match against Marske United, as the club lost 1–0. On 17 November 2021, with Blyth in the relegation zone of the National League North, Nelson left the club by mutual consent.
