He was added to a squad which was rich with attacking force and boasted such players as Iffy Onuora, Michael Boulding, Phil Jevons and Isaiah Rankin.
On 12 September 2003, Nimmo made his Grimsby debut, as a 61st-minute substitute for Jonathan Rowan in an 8–1 defeat at Hartlepool United in League One.
Nimmo played in Grimsby's next game, again as substitute, but that was his last first-team appearance before he was released at the end of the season.
[1] In August 2004 he signed for Spalding United, finishing the season as their leading scorer, before joining Wisbech Town in June 2005.
[4] After turning down a move to Boston United,[5] Nimmo returned to Holbeach in July 2008, feeling that a back injury prevented him doing himself justice at the higher level.