Loris Karius is likely to retain his starting berth in goal when Liverpool take on Southampton in the first leg of the sides' EFL Cup semi-final tie, Jürgen Klopp has confirmed.

The 23-year-old returned to action on Sunday, replacing Simon Mignolet between the sticks as the Reds were held to a 0-0 draw by Plymouth Argyle in the third round of the FA Cup.

The German shot-stopper enjoyed a comfortable afternoon at Anfield, facing just one effort on target as the hosts dominated.

But Karius could be in line for a more testing evening at St Mary's in midweek, with Klopp keen to reward his compatriot's efforts at Melwood by handing him another opportunity to shine.

"[I have made] no final decision until now, but it's pretty likely, I would say, that Loris plays again," he told reporters. 

"It's fair for his response in training, performances and all that stuff. It's likely, not sure."

LFCTV GO: Watch Klopp preview Reds' trip to Southampton

Klopp made 10 changes to his line-up for the weekend's clash with the Pilgrims, with only Emre Can retaining his place as part of the youngest starting XI in the club's history.

The manager explained that a busy schedule over Christmas contributed to his thinking in naming that team and insisted he will make a similar judgement call ahead of the trip to the south coast.

"Everybody who is ready and is good enough for the team [can play] - that's how I decide it always," he added.

"We made the changes yesterday for different reasons. I actually think there were no real alternatives for this line-up in this moment. 

"[We'd had] a little bit too many games for [some] players with matches coming up and [they were] not fit. 

"For example, Clyney [Nathaniel Clyne] nearly played all the time, Adam [Lallana] played always when he was fit but wasn't fit all the time, same as Gini [Wijnaldum]. 

"That was the decision for the line-up yesterday and so it is for the next game. 

"Both of these games are very important, I make no difference in judging these games. Wednesday, the best team we can line up [will play], that's how it is."

Klopp will also consider Sunday's meeting with Manchester United when assessing his squad, and warned he won't select any player who is not at peak fitness at Old Trafford.

"It's always who I have available and who can line up," he explained.

"It's not about young, old, whatever - it's about which line-up makes most sense because of the individual situation of the player. And the timing is very important, it's about when do we play who?

"The game against Manchester United is not possible with one or two players who are not 100 per cent fit at the moment. 

"If they are not in my plans for Southampton they [can be] in my plans, if they are close enough, for United, but that's the only thing. 

"Now we have 18, 19 players or roundabout 20 ready for the game, a few of them played yesterday and we have to see how they react and see how are the other players who were not involved for some reasons and then make the line-up. 

"Manchester United is a game like the Everton games, you can pick them out of the season and it's always a special game. 

"It's not important when it is, how much the point difference is, it's a derby and you need to be ready for this. We will be ready but, first of all, we have to play Southampton."