Liverpool manager Jurgen Klopp admitted he may have bamboozled his players by jotting down a change of tactics on a scrap of paper during his team's 1-0 defeat to Southampton in the League Cup semi-final first leg.
Striker Daniel Sturridge appeared nonplussed when passed the details on the note in the second half at St Mary's, with other Liverpool players also bemused by Klopp's switch.
Former Borussia Dortmund manager Klopp revealed he had altered Liverpool's tactics to 3-5-2, and admitted failing to get the message across to his players quickly enough.
"It was just a new system, however you want to call it, 3-5-2," said Klopp. "Two wingers, two strikers, that's all. No more information, but it was enough.
"I think we were a little bit too late when we gave him the paper when the game was already running on. That was our mistake.
"Seven or eight could see it but Roberto (Firmino) needed a bit longer. So things like this happen."
Despite the loss, Klopp insisted Liverpool will strike back against Southampton in the second leg despite being well below their best in the opening salvo of the semi-final in which Nathan Redmond's cool first half finish gave the Saints a 1-0 victory at St Mary's.
Redmond missed two more good chances as the home side wasted the opportunity to take complete control of the tie.
Relieved only to lose by one goal, Klopp knows the Anfield atmosphere will propel his players to a more dynamic effort in the return leg on January 25 and he believes that could be enough to secure a Wembley date with Manchester United or Hull.
"The performance doesn't feel too good, that's how it is.
But for the final everything is open," Klopp said.
"At this moment there's two disappointed managers after the game, one because he lost, the other because he won 1-0 and has to go to Anfield, and that's how it is.
"We will strike back, we will be a different team, different side — everything will be different at Anfield.
"So for us it's still possible to go to Wembley, and that's the target. That's the only comfort to take from tonight.
"Losing 1-0 is the third-best result you can get. I don't like it too much, but it's still possible."
Liverpool take on Manchester United at Old Trafford in the Premier League on Sunday and Klopp demanded an immediate improvement from his side, who have failed to win their last three matches in all competitions.
"I'm not used to a reaction like this from my boys but we have to accept that tonight it was not good," he said.
"We have to show a reaction against Southampton, but it would be cool to show a reaction at the weekend because we'll probably need a better performance at Old Trafford."
Southampton boss Claude Puel admitted his side should probably have secured a greater winning margin.
But the Frenchman is confident Saints can still progress to their first League Cup final since 1979.
"It's a little frustration that this win was just 1-0," Puel said. "With just a little more luck we could have been further ahead. "But I think it was important to keep this result with a clean sheet, with a win, and to sustain our chances of qualifying for the final.
"It was a great performance here, and I believe they had just one chance in the whole game, so it's a good performance from my players."