Cambridge were denied a big away victory at the death as Grimsby profited from a late penalty to draw 1-1 at Blundell Park.
Justin Amaluzor followed in a saved Jaze Kabia penalty to equalise in the sixth minute of stoppage time after Adam Mayor had put the U's ahead in the first half.
The visitors were almost gifted a goal when Darragh Burns' weak back pass fell straight to Louis Appere with a free run at goal, but the latter was stopped by Christy Pym.
Burns was denied a goal at the other end by former Grimsby goalkeeper Jake Eastwood, who stopped his curling effort after cutting in from the right flank.
Cambridge did go ahead in the 31st minute, Mayor firing first time past Pym from the edge of the box as he got on the end of James Brophy's low cross.
Grimsby were awarded a penalty in the last minute of stoppage time, and Kabia's effort from the spot was saved by Eastwood but Amaluzor followed in to knock home the rebound.
Match report supplied by PA Media
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