QPR grabbed their first ever win at Blundell Park and it could not have come in more dramatic circumstances as Eric Sabin scored in injury time.
Almost three minutes of added time had been played when Rangers poured men forward and when a shot from Kevin Gallen came back off the post sub Sabin was first on the ball and knocked it into the net.
This was the cue for some fantastic celebrations from players and supporters and Sabin was promptly booked for his over zealous celebrations.
Minutes before Sabin had been denied the clearest of penalties when hauled down in the box by Michael Edwards.
But Grimsby could feel hard done by after being pushed back for the last quarter of an hour, they dominated the game for long spells and deserved to take the three points.
But the Mariners with the season’s biggest crowd met some stern resistance and clear cut chances were few and far between.
Even so it took two splendid saves from keeper Chris Day to deny strikers Mick Boulding and Iffy Onuora.
At the other end striker Tony Thorpe shot against the bar after Paul Furlong's free kick had been pushed out by keeper Aidan Davison.
In the second half in particular it was terrific entertainment for an appreciative crowd as both sets of supporters got right behind their team.
It seemed that something must give, although a goalless draw would have pleased both teams.
But it was not to be for the brave Mariners who gave it everything as they tried to build on a recent run of seven points from nine games.
But QPR certainly showed why they are the title favourites and, with the players they have at their disposal, they are going to prove a tough nut to crack.
Unbeaten in 11 games and only one defeat this season they already look a good bet for promotion although there is a long way to go.