Liverpool manager Jurgen Klopp was in touch with the players before and after the 1-0 win over Shrewsbury at Anfield in their FA Cup fourth-round replay.
Liverpool under 23's manager Neil Critchley took charge because Klopp and his first-team squad were away on their mid-season break.
Speaking in his press conference after the game Critchley revealed Klopp was in contact before and after the game.
"The boss was in touch this afternoon with some words of advice and encouragement.
"We had a message from the staff that he is delighted with the performance and is buzzing. We have given him a game against Chelsea to look forward to.
"He just gives you total clarity, belief, play the Liverpool way, go for it. And that is what the first team do. This is us, this is how we play, this is what we stand for and you had better be ready for it."
Liverpool fielded their youngest ever starting line-up with an average age of 19 years but they dominated the game in front of a sell-out 53,000 crowd.
Midfielder James Milner was at Anfield as he continues his recovery from a hamstring injury he sustained in the third-round win over Everton.
Critchley revealed the influence Milner had in the dressing room.
"He trained with us yesterday (Monday) and he asked whether he could come along.
"He then said 'Can I come in the dressing room?'. What do you think? 'Of course'.
"He was giving words of advice, he was getting right behind the players. He was vocal in the dressing room. He was animated. He was vocal behind me, I could hear him.
"He was genuinely delighted at how the boys performed and I can't thank him enough."
Liverpool will travel to Stamford Bridge to face Chelsea in the fifth round when Jurgen Klopp is likely to mix his team with a blend of youth and experience.