Liverpool scored four first-half goals to begin their Premier League campaign in emphatic fashion against newly-promoted Norwich, but the game was not without its concerns for Jurgen Klopp. Not with so little margin for error in their rivalry with Manchester City, writes Adam Bate.

Transfer time is over and the talking is done. Jurgen Klopp had been outspoken about his frustrations with the schedule and lamented Sadio Mane’s absence but he was in no mood to make excuses before the game on Friday as the European champions kicked off their latest tilt at the Premier League title. “Now we have to be there,” said the Liverpool boss.

And there they were.

The Reds did the job on Norwich, Neville and Carragher: Liverpool defence a concern?

Of course, Manchester City will not have been too far away from their minds and not just because of last weekend’s Community Shield. This was the real resumption of their rivalry.

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Liverpool won their first six games last season and beat the bottom dozen teams in the table at home and away. They were faultless in fixtures like this one and it still wasn’t quite enough. That illustrates just how small their margin for error is, despite Klopp’s expectation that the gap between the top two and the rest will not be so big this time around.

Highlights from Liverpool's 4-1 win over Norwich in the Premier League

Highlights from Liverpool’s 4-1 win over Norwich in the Premier League

His players know that they cannot win the title in the first few games of this Premier League season but they could lose it. This emphatic start to the campaign should reduce the chance of that happening as Norwich’s naivety has already played some of the key men into form.

Mohamed Salah had looked threatening at Wembley but here he provided the finish that had been lacking that day. It is the third season in a row in which he has netted in the opening game. Here we go again. Elsewhere, Divock Origi showed he could step up, Trent Alexander-Arnold picked up another assist and Virgil van Dijk was Virgil van Dijk.

Salah doubled Liverpool's lead to score on the opening weekend yet again Salah doubled Liverpool's lead to score on the opening weekend yet again Salah doubled Liverpool’s lead to score on the opening weekend yet again

It was handy that the old favourites were there doing their thing because the game did not feature too many new arrivals. Norwich left all of their summer signings on the bench and Liverpool had hardly changed their squad. “If you don’t find the right one, don’t do it,” Klopp had said. So he didn’t. But the one new signing nobody really wanted to see was Adrian.

The back-up goalkeeper received a warm reception from the Kop but his services were required because of injury to Alisson. That is a big concern.

Alisson suffers injury scare

Klopp opted to protect Mane and if there had been any other worries, they were likely to surround Salah and Roberto Firmino after their own tournament exertions. Instead, it was Alisson who succumbed, slipping when taking a goal kick. Adrian was tidy enough despite conceding but Liverpool will not want to be without their first-choice goalkeeper for long.

“He thought something hit him in the calf, which is never a good sign,” Klopp told Sky Sports. “That means it’s probably a bit more than a strain and we’ll have to make the diagnosis tomorrow. We don’t know what it is exactly, but it doesn’t look too good.”

Alisson had to be substituted due to injury in the first half of the game Alisson had to be substituted due to injury in the first half of the game Alisson had to be substituted due to injury in the first half of the game

Alisson brought calm and control to Liverpool’s defence last season, the best in the Premier League, but for those supporters of a pessimistic persuasion there were signs of sloppiness here despite the result. In what was a curious contest, Norwich had seven attempts on goal in the first half, more than any Premier League opponent had at Anfield last season.

By the end, they’d had five shots on target. The most by any other visiting team in the past 18 months is three.

In truth, it was tough to control a game against a Norwich team playing with such reckless intent. Daniel Farke’s insistence on playing out from the back and pushing full-backs forward made for an unusually open game in which they exposed Liverpool defensively. The space between Alexander-Arnold and Joe Gomez was a worry for the home side throughout.

“Liverpool have not looked solid all pre-season,” said Jamie Carragher on co-commentary for Sky Sports. “They have been all over the place defensively,” he added. “It might seem a strange thing to say on the back of Liverpool winning 4-1 but against a better side than Norwich, more clinical, Liverpool could have lost this game.”