Liverpool manager Juergen Klopp has said there is still room for improvement if his team are to mount a serious Premier League title challenge this season despite their impressive start to the campaign.

The Merseyside club, who last won the league in 1990, demolished Hull City 5-1 on Saturday to move to fourth in the standings, five points behind leaders Manchester City.

Liverpool have won at Arsenal and Chelsea, and thumped champions Leicester City 4-1 this season, with their only defeat coming against promoted Burnley.

“I don't like standing here with all these numbers and saying 'brilliant, brilliant'. It is as good as it should be,” Klopp told Sky Sports.

“We are a good football side, but we have to improve — not only in (defending) set pieces, but in a lot of things. We have done well, but Swansea is the next challenge and it's a big challenge.

“Everybody feels good and that's good, it's better that we are all optimistic, but nothing has happened really.

Football is a nice and simple game on good days, but on other days you can't find a solution and that's what makes it interesting.” The former Borussia Dortmund boss highlighted the importance of his high-energy, counter-pressing style.

“If you win the ball back high up the pitch and you are close to the goal, it is only one pass away a really good opportunity most of the time,” Klopp said.

“So that's why I said no playmaker in the world can be as good as a good counter-pressing situation to show the players why it is so important.” Klopp also praised the all-round ability of midfielder Roberto Firmino, who has scored three goals in all competitions this season.

“Roberto is a player who is always involved in offensive and defensive actions. He really likes doing things like this (winning the ball back) because it is a natural skill that he knows,” Klopp added.

“It's a nice opportunity to win the ball and be close to the centre-backs, that's why he is doing it — he doesn't think too much, he is an instinctive player and is really, really strong in those situations.”