LIVERPOOL -- Jurgen Klopp says Virgil van Dijk had a "fairytale" Liverpool debut and revealed he initially did not plan to start the defender in the 2-1 win over Everton on Friday night.

Van Dijk made the perfect start to his Liverpool career as he headed in an 84th-minute goal to put Liverpool into the fourth round of the FA Cup.

Liverpool took the lead in the 35th minute through James Milner's penalty until Gylfi Sigurdsson equalised for the visitors in the 67th minute prior to Van Dijk's late intervention.

"A fairytale," Klopp said of Van Dijk's first outing in a Liverpool shirt at his postmatch news conference. "In a world with not a lot of fairytales anymore, I think something like that is quite special.

"It was a difficult decision to make, to be honest, because the first plan was not to start him tonight. Dejan [Lovren] and Raggy [Ragnar Klavan] played a lot of games in the last few weeks, so I changed my mind this morning. It helped.

Virgil van Dijk was the hero in his Liverpool debut. Clive Brunskill/Getty Images

"Obviously, it was a good idea in the end because the whole game was good. He showed a lot of the things we want him to show in the future very often -- heading, football-wise, first touch."

On the performance of his side at Anfield, Klopp said: "It was a big fight.

"It was not brilliant football, it was not the most beauty. It was how cup games should be. It was not who is the better side. Today, we had to really work a lot and that's all what we were asking for before the game."

Meanwhile, both Klopp and Everton boss Sam Allardyce agreed that referee Bobby Madley should not have pointed to the penalty spot in the first half when Mason Holgate brought down Adam Lallana inside the 18-yard box.

Klopp felt the situation was similar to the spot kick awarded in December's Merseyside derby, when Lovren was adjudged to have fouled Everton's Dominic Calvert-Lewin.

"A soft one, but a penalty," Klopp said. "For me, it was exactly the same situation like in the last game.

"I don't think both situations were penalties, but everyone told me the Everton one was a penalty, so I learned that this one was a penalty today."

Allardyce added: "I don't think so. I think the referee made a mistake for the first goal and we made a mistake for their winner. The rest of it, we've done brilliantly.

"I can't ask anymore from the players on their performance tonight and their desire to win the tie or at least take the tie Liverpool back to Goodison."