Klopp wanted to punch himself after he turned down Mane at Dortmund

Jurgen Klopp doesn't make the same mistake twice.

When the affable German was in charge of Borussia Dortmund he turned down the opportunity to sign Sadio Mane, then of Red Bull Salzburg, in 2014. Der BVB then made a terrible start to the season, and Klopp knew he'd made an error.

"About three months later I would have punched myself, so I already knew that the next chance I have, I would take it," Klopp told the Guardian's Andy Hunter.

Mane went on to have two successful seasons at Southampton, until he was unveiled by the now-Liverpool manager as the club's new £34-million purchase last summer.

"It was not a difficult decision," Klopp continued. "When the club came this summer and (Liverpool sporting director) Michael Edwards said we have an opportunity there were no talks necessary any more. It was a case of: 'Let's do it.' I don't know why I didn't sign him before."

He added: "I have made more mistakes in my life like this but he would have been more expensive if we had taken him to Dortmund and then he had been sold to Liverpool, so all good for Liverpool. The more I think about it, that was my first Liverpool decision. Nice."

Mane will be pitted against his former club for the first time on Saturday, with Liverpool travelling to Southampton in the latest round of Premier League matches.

Klopp admires how the Saints habitually recover from what seems like an annual exodus of their most dangerous players - this year Graziano Pelle and Mane left - but then simply restock and regroup to record improved performances in the top flight over each of the last three seasons.

"My respect for things like this is really big," Klopp shared. "I like Southampton but when I am there playing against them I don't like Southampton. That's how it is."