MatchLiverpool v Southampton: FA Cup team news
The fifth-round tie at Anfield comes hot on the heels of the Reds' extra-time victory over Chelsea in the Carabao Cup final.
Ryan Gravenberch suffered an injury at Wembley that has ruled him out of the clash with the Championship side, while the knock Wataru Endo picked up on Sunday continues to be monitored.
Darwin Nunez, Mohamed Salah and Dominik Szoboszlai also remain under assessment ahead of the game.
Klopp told Liverpoolfc.com on Tuesday: "We have a couple of niggles at least. Ryan is obviously worse. Ryan is not able to play.
"He's not running around, [he is] walking around on crutches. It's not as bad as it could have been but he's definitely out for tomorrow and for the weekend.
"Wataru obviously wasn't great after the game – it's not serious, we have to see. That's how it is with all the other boys.
"We don't want to play with that, we just have to have to do it like that. We have to wait each minute pretty much – if they feel different, stuff like this – and then we still have to make sure that we don't take too much risk.
"We are in a high-performance business, so you always take risks, you cannot play a football game without taking risks. But, of course, we want to be careful there and we have to be. So, we will see.
"It will be a much-changed team – there's no chance for anything else. But the players who featured on Sunday and are able to go again will be involved again. Easy as that."
Thiago Alcantara, Trent Alexander-Arnold, Stefan Bajcetic, Alisson Becker, Ben Doak, Curtis Jones, Diogo Jota and Joel Matip are unavailable.
Southampton, meanwhile, will be forced to make at least a pair of alterations for the 8pm GMT kick-off.
Winger Ryan Fraser joins Ross Stewart and Juan Larios on the sidelines after sustaining a knee injury during their defeat against Millwall on Saturday.
David Brooks is cup-tied, having already represented his parent club AFC Bournemouth in the competition this season.
"He's going to be out for a little bit of time, unfortunately," Saints boss Russell Martin said of Fraser at his pre-match press conference.
"Bit of a blow for us, big blow for him, but we'll have him back probably [on] the other side of the international break."
On the tie, Martin added: "I think it's one we are all looking forward to and the challenge for us is to be the team we want to be – to go there and be brave and be aggressive. We'll see where it will take us."
Last match
Chelsea 0-1 Liverpool (February 25): Kelleher, Bradley, Konate, Van Dijk, Robertson, Endo, Mac Allister, Gravenberch, Elliott, Diaz, Gakpo.
Southampton 1-2 Millwall (February 24): Bazunu, Harwood-Bellis, Stephens, Bednarek, Walker-Peters, Smallbone, Aribo, S. Armstrong, Brooks, Fraser, Adams.
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