Cropper who has been out with injury since the emphatic 3-1 away win at Scunthorpe, has failed to regain his first team place and goes straight into the Trinity side to play Frickley Athletic in the Unibond Premier League on tuesday evening.
Cropper becomes yet another link between The Imps and Trinity. Defender Mark Camm and former striker Adie Mike also spent time at The Northolme last season and ex-goalkeeper Paul Pettinger signed for them on a free transfer but soon moved to Kettering Town.