Postpublished at 09:56 British Summer Time
We'll return to the Grimsby v Man Utd fallout shortly but a little transfer news first...
Reaction after Man Utd knocked out of EFL Cup by Grimsby Town
League Two side win 12-11 on penalties after 2-2 draw in normal time
United boss Ruben Amorim under pressure and admits his team were 'completely lost'
Manager criticised for staying in dugout during penalties; with new signing Benjamin Sesko the 10th player to step up
Grimsby's reward is a trip to Sheffield Wednesday I Third round draw
Rangers out of the Champions League play-offs after being thrashed 6-0 by Club Brugge
Brighton manager Fabian Hurzeler says he is 100% confident midfielder Carlos Baleba will stay at club despite interest from Man Utd
Q&A: Chief football writer Phil McNulty has been answering your questions
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Ben Collins, Craig Nelson, Karan Vinod and Ben Ramsdale
We'll return to the Grimsby v Man Utd fallout shortly but a little transfer news first...
Grimsby Town 2-2 Man Utd (Grimsby win 12-11 on pens)
Grimsby Town
Spare a thought for Grimsby goalkeeper Christy Pym. He saved one penalty and scored his own in the shootout, before telling Sky Sports: "I'm a Man Utd fan, so I'm half-fuming a little bit.
"It's not sunk in yet. Nights like this are what you play football for. Just brilliant.
"I should have done a little bit better [in the shootout], shouldn't I? I made one save to keep us in it and the boys have done the rest. It's brilliant."
Grimsby Town 2-2 Man Utd (Grimsby win 12-11 on pens)
BBC 5 Live Breakfast
Grimsby Town manager David Artell described Wednesday's Carabao Cup win over Manchester United as a "fantastic night for the whole town".
He told 5 Live Breakfast: "It was a crazy night. The old girl Blundell Park was rocking. It was a fantastic night for the whole town - the community and everyone associated with the football club."
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As a fan you should always back the manager, but Amorim's responses in the interviews (which he repeated multiple times) and his cowardice in not watching the penalties, that's not someone leading from the front, that's someone that looks like he's cracked under pressure, makes me think he will walk.
Stuart, Manchester
Grimsby Town 2-2 Man Utd (Grimsby win 12-11 on pens)
Speaking on BBC Radio 5 Live, Manchester United boss Ruben Amorim added: "[I have] no more answers. I do not even have anything to say. I just want to apologise to our fans. I'm really, really sorry.
"We played well against Arsenal and then we should have won against Fulham. Then to come here in the League Cup when everything is so important in this moment because everything is so scrutinised and we performed like that.
"I think my players spoke really loud about what they want and what they don't want."
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It's probably been said before, but Liverpool looked at Amorim as a replacement for Klopp but decided not to pursue him. Firstly, I am grateful, but the big question is why?
Jon
Grimsby Town 2-2 Man Utd (Grimsby win 12-11 on pens)
BBC Radio 5 Live
Manchester United boss Ruben Amorim's biggest problem is that there are multiple issues to address. Some directly relate to personnel and others have resurfaced around players being able to carry out his tactics.
Andre Onana's performance in goal only underlined why United have been looking at a deal for Belgian goalkeeper Senne Lammens.
The Cameroon international should have done better for both Grimsby goals and exhibited the same vulnerability in dealing with crosses that underscored back-up Altay Bayindir's performances against Arsenal and Fulham.
Here's what the pundits had to say:
Former Manchester United forward Dion Dublin on BBC Radio 5 Live: "I don't know what Onana is doing.
"For the second goal there is nothing at all, just a half-hearted attempt. I would be absolutely livid with my keeper doing that. I would expect to get smashed out of the way if my keeper is coming for a cross. But there was nothing at all."
Former Blackburn and Celtic striker Chris Sutton added: "What an embarrassment for Manchester United. Where does Ruben Amorim go from here? I think he will struggle to come back from this. People will hold this against him.
"The pressure this season for Ruben Amorim now is well and truly on. With massive games coming up, if I'm him I'm officially worried."
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Amorim will survive this; however, it's whether or not he wants to be there anymore. Only Maguire and the new players showed any passion. The rest just don't care and just take a wage. Club's unsavable.
Cal
I feel for Amorim in some respects because he has a clear identity of what he wants to do. But his stubbornness with his system will be his undoing. Not helped by certain players either, and poor recruitment, especially in the goalkeeping department.
Thomas
Grimsby Town 2-2 Man Utd (Grimsby win 12-11 on pens)
After Manchester United's shock defeat, boss Ruben Amorim said: "I think this is a little bit the limit. I think something has to change.
"I think the team and the players spoke really loud today, so that's it. [Tonight] I think the best team won, the only team that was on the pitch.
"I think it's really clear what they spoke, so let's move on from this day. I think it was clear for everybody what happened today.
"The way we start the game without any intensity, we were completely lost. In this moment, we need to focus on the weekend and then we have time to think."
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Sometimes you have to hit rock bottom to move forward.
Justin
Is this "rock bottom" for Man United? Or have they further to fall? I'm old enough to remember them getting relegated from the top flight, so nothing's impossible.
David
Grimsby Town 2-2 Man Utd (Grimsby win 12-11 on pens)
In days gone by, Manchester United might have fielded a bunch of kids in the second round of the EFL Cup.
Not so much of that last night. Boss Ruben Amorim named a fairly strong starting line-up and also brought on three senior players as early as half-time, with his side already trailing 2-0.
Man Utd's starting XI: A Onana, A Heaven (M Mount 64), H Maguire, T Fredricson (Bruno Fernandes 45), Diogo Dalot, M Ugarte (B Mbeumo 45), K Mainoo, P Dorgu (M de Ligt 45), Matheus Cunha, B Sesko, A Diallo (J Zirkzee 82).
Subs not used: Casemiro, A Bayindir, T Heaton, L Leon.
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Got a question about Manchester United? What next after their defeat to Grimsby Town?
Or maybe you want to hear about the latest transfer moves or some other burning issue?
Our chief football writer Phil McNulty will be on hand a bit later to answer your queries - so send in your questions by clicking the link at the top of this page.
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After 30 odd years of "We're Man United, we'll do what we want" under Fergie, I have to say that this fall from grace is both deserved and hilarious!
Mike
Honestly, I haven't stopped laughing since last night. Looking at the line-up, and it's not as if it was the kids playing. I think this may be the worst result EVER in football. Well done Grimsby
Chris
You make a good point about United's starting line-up Chris, but worst result EVER in football... that seems a stretch.
Grimsby Town 2-2 Man Utd (Grimsby win 12-11 on pens)
Simon Stone
BBC Sport Chief Football Writer at Blundell Park
Amid the recriminations at Old Trafford, Grimsby should not be denied due praise for their glory night.
From the first whistle, it became clear Mariners boss David Artell's gameplan was to heap as much pressure around the visitors' area as possible, knowing the home fans would seize on any opportunity they could to whip up an already intense atmosphere.
For a game in which they could have sold out their 9,000-capacity stadium three times over, the supporters, who have had to endure two relegations to the National League in the last decade and a half, lived up to the promise of chief executive Polly Bancroft by 'making life uncomfortable' for her old club.
It was 1948 when these two sides last met, so the vast majority witnessing this occasion have never seen Manchester United at this stadium before.
They could scarcely believe it as Charles Vernam and Tyrell Warren scored. Yet Grimsby deserved their advantage and had avoided being swamped in the second half despite the multi-millionaires in opposition before Bryan Mbeumo and Harry Maguire threatened to ruin their night.
But Grimsby were not to be denied. This was a night no-one who was here will ever forget.
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Congratulations to Grimsby. A great night for them, but so far, three games into the season, United have conceded four goals, and three of them have been down to glaring goalkeeper errors. This was a weakness last season, and it should have been a priority in this transfer window.
Mike
Played weeks beginning 15 & 22 September, with Champions League and Europa League fixtures also scheduled during this period
Grimsby's reward for beating Manchester United is a visit to Sheffield Wednesday in the EFL Cup third round.
Holders Newcastle will start the defence of their crown at home to League One side Bradford.
Manchester City will take on League One Huddersfield Town at the Accu Stadium while Arsenal will travel to Port Vale.
Reigning Premier League champions Liverpool, who were beaten in last season's final, will host Championship Southampton, while Chelsea have been handed a trip to Lincoln City.
Third-round draw in full:
Manchester United may have been dumped out of the EFL Cup last night but there were no dramas for the other three Premier League clubs involved, although kick-off at Hill Dickinson Stadium was delayed by 15 minutes to ensure all supporters had safe access into Everton's new home:
Club Brugge 6-0 Rangers (Agg: 9-1)
Pat Nevin, Nedum Onuoha and James McFadden discussed Rangers' defending against Club Brugge as they suffered a brutal 6-0 loss in the second leg of their Champions League play-off tie.
Nevin said Rangers' mistakes were "groundhog day... again". He added that their defending was "schoolboy, amateurish, not doing the simple things".
'It's amateurish' - MOTD pundits react to Rangers defending against Club Brugge
Club Brugge 6-0 Rangers (Agg: 9-1)
Nick McPheat
BBC Sport Scotland
Russell Martin's hapless 10-man Rangers crashed out of the Champions League play-offs in humiliating fashion as a record-equalling six-goal European loss at relentless Club Brugge.
Before the match, head coach Martin insisted everyone at Rangers was "calm" amid a troubling start to the season, but many fans will be anything but with Celtic set to visit Govan on Sunday.
A calamitous opening eight minutes in Belgium epitomised Martin's alarming introduction as boss, with Rangers on the way to a five-goal deficit by half-time.
Martin reshuffled his team into a 5-4-0 shape at the break, but that did not prevent the sensational Christos Tzolis squeezing through the backline and clipping in a sixth just five minutes after the interval.
Champions League highlights: Club Brugge 6-0 Rangers (Agg 9-1)
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We're about to bring you more reaction from Rangers and the EFL Cup, but we also want to hear your thoughts on Grimsby's famous win. What is the cupset of all cupsets?
And what does it mean for Manchester United and their boss Ruben Amorim?