MatchLiverpool v Nottingham Forest: Team news
A muscle injury is set to sideline Firmino for the Reds' next three games, with meetings with West Ham United and Tottenham Hotspur quickly following the visit of Steve Cooper's side.
During his pre-Forest press conference on Friday, Klopp revealed: "Unfortunately Bobby picked up a muscle issue a little bit.
"We will see how long that takes. It's not too serious but he is definitely out for tomorrow and next week we have two more games, I would say they are impossible as well and then we will see. We have to take it day by day."
Firmino's absence leaves Klopp with five senior forwards to choose from: Luis Diaz, Cody Gakpo, Diogo Jota, Darwin Nunez and Mohamed Salah.
"The ticket into this team must be - and will be, definitely, again - counter-pressing. That's how everything started… I saw so many games from us where I didn't like that and that's a pretty strict thing," Klopp explained, when asked how he will decide which of that quintet starts.
"All five now available, and especially with Bobby all six, can do that pretty well but if you do it in the game you play, you have a chance to start again. So, that's it. But we have opportunities to change of course and we will see how we do that.
"Now we have to change [because] in the next two weeks we have five games so yes, there will be changes and that's good. Hopefully we can have at least these five and maybe from a moment on six again. That would be absolutely great but everybody will play, everybody is super-important to us."
The boss was also quizzed on the fact Harvey Elliott has not featured in Liverpool's last three outings.
Klopp replied: "He's training exceptionally. Fabio Carvalho is training exceptionally, to be honest. All the boys [are].
"That's the hardest part, [we] never had it the whole season and now we have it and all of a sudden I leave five players at home and they are all of a sudden not even in your squad. Crazy! Harvey is very, very close; absolutely close to starting again."
If Fabinho receives his 10th booking of the Premier League season on Saturday he would be suspended for the games against West Ham and Tottenham.
Meanwhile, Forest head coach Cooper will have the same crop of players to choose from that were available for last weekend's home defeat by Manchester United.
It means Cheikhou Kouyate, Gustavo Scarpa, Ryan Yates, Serge Aurier, Chris Wood, Willy Boly, Dean Henderson, Omar Richards and Giulian Biancone are set to miss the 3pm BST kick-off in L4.
"We've had no new injuries and nobody is quite ready enough to return," Cooper told the media on Thursday. "We're as we were before the Manchester United game.
"We know all about the stats and know our away form has been nowhere near good enough, but as each game comes I ask myself and staff and the players to give their best and really believe in the plan and believe we can achieve to get a positive result.
"If we go into the game with those things in our mind, we've got zero chance. If we go in thinking about doing things right, then we give ourselves a chance of winning any game."
Last match
Leeds United 1-6 Liverpool (April 17): Alisson, Alexander-Arnold, Konate, Van Dijk, Robertson, Fabinho, Henderson, Jones, Jota, Salah, Gakpo.
Nottm Forest 0-2 Manchester United (April 16): Navas, Felipe, Niakhate, McKenna, Williams, Freuler, Danilo, Lodi, Gibbs-White, Johnson, Awoniyi.
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