Liverpool will have several reasons to be wary of Tottenham Hotspur on Sunday. But midweek provided a reminder that the north London side have lost their biggest threat.

Harry Kane's penalty in Bayern Munich's 2-2 Champions League semi-final first-leg draw at home to Real Madrid was the England captain's 43rd goal in as many matches since his move to Germany last summer.

Liverpool would have been glad to see the back of Kane. He scored nine goals in 16 appearances against them for Tottenham and despite winning just one of those games, he was always a dangerman when they two sides faced off.

But he wasn't the only one, and the Reds might be just as worried about Kane's old partner in crime, the ever-impressive Heung-Min Son.

Son may be considered one of the nicer players in the Premier League, but Liverpool and their departing Jurgen Klopp still have reason to be sick of the sight of the South Korean forward. He has, after all, scored five goals in his last six Premier League appearances against the Reds, and six in 14 appearances in total for Spurs, while he returned five goals from five starts against the Klopp's Borussia Dortmund.

Yet while Son would remain unbeaten when starting against the German boss in the Bundesliga during his time with Hamburg and Bayer Leverkusen, it’s a different story from his meetings with the Reds.

Locking horns with Liverpool on 16 occasions, Tottenham's infamous 4-1 victory at Wembley in October 2017, in which he scored, and then their controversial 2-1 home triumph in September, in which he scored again, are the only times Son has ended up on the winning side against the Reds. And of course, such a run includes Spurs' defeat in the 2019 Champions League final.

Still, a record of 11 goals from 17 starts in all competitions against Klopp teams ensure Son is a dangerman who could deal their hopes of returning to winning ways a big blow if he maintains such a scoring one at Anfield on Sunday. And one Klopp knows is near impossible to stop.

"I will be prepared for the best possible Tottenham side,” the Liverpool manager told reporters before facing Tottenahm last season. “They were, for some years, by some distance the best counter-attacking team in Europe.

“There were moments when you lost the ball, they only had to find Harry Kane and the next moment Son was in a one v one situation with the goalie. No clue how to defend that properly, best way not to lose the ball.”

As a result, is it any wonder that Klopp wishes he had signed Son earlier in his career?

“One of the biggest mistakes in my life is not signing Son Heung-min,” he rued to Korean outlet KBS News in November 2021. “Outstanding player. He is fantastic, a sign of Korean football and one of the best strikers in the world.”

Klopp failed to sign Son for Dortmund in 2013, with the player opting to join Leverkusen from Hamburg instead in a €10m deal.

“I wanted to stay in the Bundesliga. Leverkusen and Dortmund wanted me,” Son later recalled when explaining his decision to snub Klopp. “Both teams play in the Champions League but I thought Dortmund would use rotation more than Leverkusen.

“That's why I chose Leverkusen over Dortmund. It's really important to play regularly at my age.”

Two years later, having scored 29 goals across two campaigns for Leverkusen, he would sign for Spurs for £22m in the same summer that Klopp left the Bundesliga. Now, a Tottenham Premier League legend, he boasts 161 goals from 403 appearances across nine seasons. But crucially, no trophies.

Given Klopp’s admiration for Son, Liverpool have sporadically been linked with his services over the years. Yet, now 31-years-old, and the boss leaving in the summer, that ship seems to have long since sailed.

But while Klopp might consider it one of his ‘biggest mistakes’ not signing Son, the Reds will have no regrets. Son is the same age as their famous, now dismantled, attacking triumvirate of Roberto Firmino, Sadio Mane and Mohamed Salah after all.

Firmino would make his own switch from Bundesliga to Premier League the same summer as Son, joining Liverpool for £29m from Hoffenheim. Enduring a slow start, partly because of injury, once Klopp took over as manager in October 2015 and inherited the Brazilian, Firmino was revitalised and became a legend at the club.

As for Mane, he was snapped up from Southampton for £34m in the summer of 2016. Klopp had previously tried to sign the Senegalese for Dortmund, as he had also attempted with Son, only to decide against the switch. Klopp would later admit he could have punched himself for such a decision, and made sure to make amends at Anfield, righting a wrong that he couldn’t with regards to Son, once he became available.

Mane would register 120 goals and 38 assists from 269 appearances for Liverpool before leaving for Bayern Munich in a £35m switch. Meanwhile, Salah signed from AS Roma for £43.9m in the summer of 2017. He currently boasts 210 goals in 346 appearances and is already regarded as one of the greatest players in the club’s history.

Between them, the trio would help transform the Reds’ fortunes under Klopp. While Firmino and Mane would help get Liverpool back into the Champions League, the addition of Salah contributed to their transformation into one of Europe’s strongest sides.

All three would win every major honour on offer to them under Klopp as the Reds were crowned champions of England, Europe, and the world.

Admittedly, if you are being greedy, you could be forgiven for wondering what else Liverpool might have won had they possessed Son’s talents to compliment their then-undroppable front-line. He is certainly a player that suits Klopp’s demands, after all.

Yet apart from a few admiring glances of their own, Kopites have never had to wonder what could have been when it comes to the South Korea captain. They are more than happy with the hand Liverpool were dealt.

Whether Son has any regrets of his own, given his lack of silverware compared to his Reds counterparts, only he can say. It is worth noting though that even if he hadn’t turned down Klopp and Dortmund’s advances in 2013, that doesn’t mean he would have followed the manager to Anfield. Likewise, had he not left Leverkusen when he did, it’s impossible to know if Klopp would have reignited interest in Son’s services following his own arrival at Anfield.

Son might be a big mistake for Klopp but there are no Reds regrets. He could have potentially been part of this Anfield story, but instead he is just an admired foe, watching on from afar as Liverpool won everything there is to win, with Europe’s biggest prize even coming at his expense.

A version of this article was first published in April 2023