Simon Grand's late header secured Southport a point at home to Grimsby on the opening day of the season.
The visitors had the better of the first half and went close through Andy Cook, while the same man was denied by keeper Tony McMillan after the break.
Grimsby went ahead 16 minutes from time when Craig Disley turned in a low cross from Aswad Thomas.
With time running out, Grand headed the equaliser from six yards as he converted Shaun Whalley's free-kick.
VIEW FROM THE DRESSING ROOM
Grimsby Town joint manager Rob Scott told BBC Radio Humberside:
"I thought we played well and I thought for large chunks of the game we dictated the play.
"It's disappointing that we conceded from a corner and it's a free header.
"I don't want to be too harsh on them as I think we played extremely well and, on another day, we win the game.
"But we haven't done and we've come away from a very hard venue with a point."
Southport 01 McMillan 02 Smith 03 Lever 04 Akrigg 05 Parry Booked 06 Grand 07 Whalley 12 Benjamin Booked (Ledsham - 60' ) 16 Moogan (Chalmers - 69' ) 10 Gray (Almond - 67' ) 19 Bakare Substitutes 13 Nemes 17 Lynch 08 Ledsham 15 Chalmers 11 Almond Grimsby Town 13 McKeown 03 Thomas 18 Pearson (Soares - 85' ) 19 Wood 22 Pond 04 Niven 07 Colbeck 08 Disley Booked 11 Artus Booked 05 Pearson 12 Cook (Elding - 70' ) Substitutes 02 Hatton 06 Miller 17 Soares 21 Chanoj 09 Elding
Ref: Seb Stockbridge