“ONE OF THE BIGGEST CUPSETS EVER!” screamed the Carabao Cup social media accounts.

United had never lost to a fourth-tier team in the EFL Cup, and were playing in the second round for the first time since 2014.

Manchester United may not be in Europe, may have finished 15th in the Premier League last season and may be winless this season.

But they would still have been expected to win this, and were 1-7 odds to win the match in 90 minutes.

In the end they were lucky not to lose in 90 minutes.

United have won 20 league titles, 19 domestic cups, three European Cups and various other bits and pieces.

Grimsby’s highlights are the Second Division titles they won in 1901 and 1934 – and most recently the 1998 Auto Windscreens Shields Trophy.

Transfermarkt reckon Grimsby’s squad is worth £3.1m, compared to United’s £765m players.

But they levelled the playing field in their own stadium, which has a capacity of just over 10% that of Old Trafford.

Sutton, who once managed Grimsby’s local rivals Lincoln City, said: “Credit to David Artell. Credit to the Grimsby players. They were true to his word.

“It is one thing saying it [that you’re going to stick to your style of play], but it’s a whole other thing for the players to go out against Premier League opposition, big stars, and actually have the courage to take them on, push them back and show that belief.

“There was no inferiority complex from Grimsby, far from it. If anything it was the other way around.”

Former United striker Dion Dublin on 5 Live added: “Overall if there is a percentage on this game, the game itself, I think Grimsby nicked it 60-40, perhaps even more than that.

“With all the effort that they put into the first half I think they deserved to get past this immovable object you would expected to have seen in Manchester United.

“Grimsby, the way that they were organised, fully deserved this.”