Liverpool manager Jurgen Klopp said he is not too concerned over his side's defending as they head to Porto for their second Champions League group match.

The Premier League leaders’ wild 3-3 draw at Premier League newcomers Brentford on Saturday was the first time they had conceded three in a match since the European defeat to Real Madrid in April.

It came as something of a shock after previously letting in just one in five league matches this season.

However, they have already experienced similar against AC Milan a fortnight ago when they let in two goals in three minutes just before the interval, resulting in a more difficult second half than they should have had before closing out a 3-2 victory.

"It’s not that much of a concern because I don’t think you should make these things bigger than they are – but we have to show a reaction, that’s for sure," said Klopp before the squad flew out to Portugal.

"It’s really tricky to win a football game when you are not defending on your highest level and that’s what we didn’t do.

"The common opinion is it’s only about the last line but we had a problem in general with our defending. That’s why Brentford caused us problems and it wasn’t good.

"We have to improve in that department for sure but now is not the moment to be concerned.

"We spoke about it and we know we cannot do it like that. I think we have sorted it but we have to show it tomorrow."

There is the potential for more defensive disruption as Klopp is likely to rotate his players, with Joe Gomez and Ibrahima Konate in contention to come in at centre-back.

Liverpool’s last two meetings with Porto have seen them score 11 goals and concede just one and after both encounters Klopp’s side progressed to the final, winning one and losing one.

Fit-again midfielder Naby Keita was included in the squad after recovering from the foot injury which forced him to miss the Brentford game.

The Guinea international missed the Brentford game with a foot injury sustained in the midweek Carabao Cup win at Norwich.

Wales right-back Neco Williams, who has been sidelined all season by an ankle injury, also trained before the flight to Porto.

Opposition manager Sergio Conceicao insists they will try to target Liverpool's weaknesses as they look to level up the imbalance they face on and off the field.

"If we look at Liverpool’s experience, since 2019 they have lost (Dejan) Lovren and (Georginio) Wijnaldum," he said. "We were left with three: (Jesus Manuel) Corona, Otavio and Bruno Costa.

"That experience and the fact that they stay together is very important in a competition like this.

"We can highlight numerous theoretical differences, such as the fact that our budget is 20 or 30% of Liverpool’s, but that will not come into play tomorrow.

"What comes in is the preparation of the game, the strategy we define and the way we are going to be organised.

"We have to be as competitive as Liverpool, an opponent who, for me, is the best team in the world at some moments in the game – and I’m not exaggerating Liverpool’s value.

"It’s up to us to counter that opponent’s power and expose some of the opponent’s weaknesses, because they also exist."

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