It was an open-and-shut case for many, including his manager.

Mohamed Salah was, it was declared on an almost weekly basis, the best soccer player in the world for the first half of this season, demonstrating the kind of elite-level scoring form only Lionel Messi, Cristiano Ronaldo and more recently Robert Lewandowski have been able to produce this century.

It wasn’t just the volume of goals – 22 in his first 23 matches – that he was putting away for Liverpool. It was the sheer quality of them that took one’s breath away.

None more so than the weaving solo effort he conjured up against Manchester City at Anfield in October, midway through a run of 10 straight games when he scored, that surely will go down as the Premier League’s goal of the season.

”Come on,” Liverpool manager Jurgen Klopp asked out loud, ”who is better than him?”

Fast forward six months and Salah is, in relative terms, in a rut. Indeed, heading into a seismic return match against City on Sunday that could yet determine the destination of the title, there’s an argument to say he might not even be Klopp’s go-to striker.

There are potentially a whole host of reasons why Salah is going through his worst scoring run this season, with no goals in five games in all competitions and no open-play goals in six weeks.

Is he tired? He’s already played 47 games this season, after all.

Are painful losses for Egypt lingering? First there was the penalty-shootout loss to Liverpool teammate Sadio Mane’s Senegal in theAfrican Cup of Nations final in February, then a loss – also via a shootout – to the same opponent in a World Cup playoff last month.

Does it have anything to do with his current contract standoff with Liverpool? That would be unlikely.

Maybe it’s simply the vagaries of form and happenstance. Because he’s still piling up the chances, just not converting them.

Whatever it is, this is not the Salah of six months ago. He was substituted midway through the second half in each of Liverpool’s last two games after, by his high standards, fairly underwhelming performances.

”Sometimes he could decide in a better way, no doubt about that, pass the ball quicker and all these things,” Klopp said this week. ”But it’s a tough period for Sadio (Mane) and Mo, with the Africa Cup and coming back being immediately available for us again with all the games.

”It’s completely normal in a season that you have these little (ups and downs).”

Will Klopp drop Salah against City on Sunday? He’d be a brave man to do that to the Premier League’s top scorer. But it’s not that he doesn’t have options.

And in Diogo Jota, Klopp has a forward who has helped to take on Liverpool’s scoring burden firstly while Salah was away at the African Cup and then amid the Egyptian’s recent struggles.

Jota appears to be Liverpool’s first-choice center forward now, displacing Roberto Firmino by doing all the dirty work like the Brazilian – the tracking back, the pressing, the harrying of defenders – but scoring a lot more goals at the same time.

Jota has scored four goals in his last six games, including the winner against Nottingham Forest in the FA Cup quarterfinals and crucial openers against Arsenal and Watford in the league. He is tied for second in the league’s scoring chart with 14 goals.

Rested against Benfica in the Champions League in midweek, Jota is highly likely to start against City. It’s which two players are alongside him in the three-pronged forward line that’s the big question.

And this is where Liverpool holds the edge over City, which will start the game at Etihad Stadium one point clear of Klopp’s team with eight games left. Liverpool’s firepower simply is greater, with Klopp able to call upon Salah, Jota, Firmino, Mane and January signing Luis Diaz, who has settled in seamlessly since joining from Porto.

City has a slew of classy attacking midfielders and forwards but none have the cutting edge of the likes of Salah – when he’s in form – or Jota.

City manager Pep Guardiola knows a draw is enough to leave the destiny of the title solely in his team’s hands. If that happens, City will win the league by winning its next seven games.

The onus is on Liverpool to go on the attack, which makes the game all the more enticing for fans.

And Klopp, who boldly played a front four of Mane, Salah, Jota and Firmino at the Etihad two seasons ago, knows he has the offensive players to overwhelm City.

Whether Salah is playing or not.

More AP soccer: https://apnews.com/hub/soccer and https://twitter.com/AP-Sports