The 23-year-old new signing slid home Federico Chiesa's pass five minutes from time to seal a 2-1 win over second-tier Southampton as Liverpool produced another late show at Anfield on Tuesday.

The France forward had replaced £125-million ($168 million) British-record signing Alexander Isak at half-time after the Sweden international opened his account for the club.

Ekitike's first involvement was to be booked for punching the ball away in frustration.

Shea Charles equalised but Ekitike scored the winner in the 85th minute -- wheeling away to the corner flag and removing his shirt before holding it up for the cameras.

Referee Thomas Bramall had no option but to issue a second caution followed by a red card, meaning the forward will be suspended for the Premier League leaders' trip to Crystal Palace on Saturday.

A shame-faced Ekitike, who signed for the club in July for £69 million, said he had got carried away.

"I was so excited tonight to help the team achieve another victory here in our home for my first Carabao Cup (League Cup) match," he posted on Instagram.

"The emotion got the better of me tonight," he added. "My apologies to all the Red family."

Liverpool manager Slot was distinctly unimpressed, labelling Ekitike's behaviour in the third-round tie "needless" and "stupid".

"I told him that if you score in the Champions League final in the 87th minute after outplaying three players and hitting it in the top corner I can maybe understand," he said.

"He is like, 'This is all about me, what did I do'?

"But I am old-fashioned, I'm 47 and old. I never played at this level but did score a few goals and if I scored a goal like this, I'd have turned around and walked up to Federico Chiesa and said: 'This goal is all about you, this is not about me'."

Ekitike has started the season well, with three goals in five Premier League games.

But he is locked in a battle for a forward slot with Isak and can ill afford to miss games, with the Swede eager to make his mark.