Grimsby have sealed Gary Croft's return to Blundell Park on a two-year deal, subject to him remaining injury-free.
Grimsby sold Croft to Blackburn for £1.7m
Croft, 31, left the Mariners in a £1.7m move to Blackburn in 1996, and played more than 50 games for Rovers before a £500,000 move to Ipswich in 1999.
After loan spells at Wigan and Cardiff, Croft moved to Ninian Park on a free transfer in 2002.
Mariners' boss Russell Slade has also snapped up striker Calvin Andrew on a short-term, one-month contract.