Liverpool raised a few eyebrows this summer when, after winning the Champions League, they opted not to make a high-profile signing.

In truth, there aren’t too many players in world football who would strengthen Jurgen Klopp’s starting line-up right now.

The German has assembled an XI capable to reaching back-to-back Champions League finals and racking up 97 points in the Premier League.

And it’s been thanks to the club’s incredible transfer business in recent years.

Pretty much every single high-profile signing has been a success.

Roberto Firmino, James Milner, Joe Gomez, Sadio Mane, Georginio Wijnaldum, Joel Matip, Virgil van Dijk, Mohamed Salah, Andrew Robertson, Alisson and Fabinho have all arrived in recent years and have been huge successes at Anfield.

Klopp has overseen many of those arrivals along with sporting director Michael Edwards.

But who has been Klopp’s best signing been whilst in charge of the Reds?

There are certainly plenty of candidates but Jamie Carragher thinks it’s Sadio Mane.

“The most important signing during Jurgen Klopp’s entire tenure as Liverpool manager?” Carragher asked in his Telegraph column.

You could make a strong case obviously for Mohamed Salah, Virgil van Dijk or Alisson following the incremental improvement that has coincided with each of their arrivals, but I still maintain that the correct answer to this particular question is Sadio Mane.

Carragher went on to sing the praises of the Senegalese star, claiming that he’s Liverpool best winger since John Barnes.

"So how do you define ‘world class’? I judge it by thinking about a fantasy world starting XI and whether any given player would either get straight into the team or at least be in the best two or three in the world in their position," Carragher added.

"As left-sided attackers I would rate Mane, Raheem Sterling and Eden Hazard as currently the best, especially now that Ronaldo has become more of a striker and the struggles of Neymarsince the World Cup.

"I also think that Mane is Liverpool’s first genuinely world-class winger since John Barnes and the club’s best wide left player for almost 30 years."