Liverpool manager Jurgen Klopp has warned the EFL he will quit the Carabao Cup if their packed fixture schedule is not treated sympathetically.
The Reds moved into the quarter-finals with with a 5-4 penalty shootout win over Arsenal, after a thrilling 5-5 draw at Anfield.
But there was little time to celebrate before Klopp was expressing his concern about the scheduling of their next tie.
Match dates for the last-eight round are scheduled for the week commencing December 16, when Liverpool will be in Qatar at the Fifa Club World Cup.
And Klopp said if a suitable alternative, the most likely being week commencing January 6, the scheduled date for the first leg of the semi-final, could not be found then they would refuse to play.
"Fifa told us the Club World Cup will be there [Qatar] and we have to come there and we will do," said Klopp.
"The Premier League tells us we have to play in the Premier League, which we do obviously.
"The Carabao Cup, if they don't find an appropriate place for us – not 3am on Christmas Day – then we don't play it.
"We will not be the victim of this problem. If they don't find a proper date for us, then we cannot play the next round and whoever is our opponent will go through – or Arsenal play them."
It seems highly unlikely the EFL would run the risk of allowing Klopp to carry out his threat, considering the commercial and television appeal the record eight-time winners of the competition carry.
But Klopp has put the ball firmly in the organiser's court and given them plenty of warning of the potential consequences.
After their action-packed game at Anfield the EFL will not want their competition to reach its final stages without one if its main draws.
The game swung one way and then the other as after Shkodran Mustafi's own goal Arsenal took a 3-1 lead thanks to a double from Gabriel Martinelli and one from Lucas Torreira, before James Milner's penalty just before the break.
Ainsley Maitland-Niles restored the Gunners' two-goal cushion, two goals in four minutes from Alex Oxlade-Chamberlain and Origi levelled things up and after Joe Willock scored a goal worthy of winning such a entertaining encounter Origi volleyed home in the fourth added minute to set up a shootout.
Only substitute Dani Ceballos missed, leaving Scouser and academy graduate Curtis Jones had the honour of scoring the winner in front of the Kop.
Mesut Ozil, making only his third appearance of the season, had a hand in three of Arsenal's goals but was withdrawn with Liverpool on top at 4-4.
It was the first time the former Germany international had featured in a match-day squad since the last round of the Carabao Cup, although mananger Unai Emery claims he remains in contention for Premier League games.
"We had decided beforehand [to take off Ozil]. He worked well in 65 minutes," he said. "Ozil played very well. He played a very good match. We are going to play on Saturday and in my mind there's the possibility to use him again."
Defeat for Arsenal, having twice conceded a two-goal lead, put more scrutiny on Emery who since drawing 2-2 against Crystal Palace, having also been 2-0 up at the weekend, has spent most of his time deflecting questions about whether Granit Xhaka should still be captain after his furious reaction to supporters on being substituted.
He put on a brave face afterwards, however, saying: "As a supporter, I enjoyed it. It was a very good performance [in the first half] from us.
"We can't be 100 per cent happy with our defensive work but when you play in games like tonight's, fans can be happy with the performance of the two teams. We were very close to the win.
"The dressing room is very flat because we were so close to winning. We were taking confidence in the first half."