Liverpool completed their first business of the January window by signing Porto's Luis Diaz on Sunday.

The Colombian winger, 25, has been the Portuguese giants' shining light over the past three seasons and cost the Reds £37million before add-ons.

So why did Jurgen Klopp push for the signing of Diaz so hard?

Spurred on by rivals

Liverpool were not planning on moving for Diaz now, according to many reports.

But Tottenham’s desire to sign the Colombian meant they were forced to act quickly to avoid missing out on a player Klopp wanted.

The German said: "I could not be happier that we’ve been able to get this deal done and bring Luis to Liverpool.

"I have always been a believer in only signing players in January if you would want to sign them in the summer, and that’s very much the case with Luis.

"He is an outstanding player and someone we’ve been tracking for a very long time."

Top of the Klopps

Liverpool rarely sign duds — especially when they spend this much on a player.

As well as detailing why they had signed Diaz now, Klopp went on to sing the praises of the winger.

He featured against the Reds in both of their Champions League group games, leaving the German and his players impressed.

He added: "We believe he has everything needed to fit into our way and adapt to the Premier League, both physically and mentally.

"He is a player who is hungry for success and knows you have to fight to get what you want. He is a fighter, no doubt. He’s a skillful team player who always has the goal in mind.

"This team deserved to add quality and when we played against Luis earlier this season, we saw what a danger he is, how fast he is and how his mentality was to help his team. 

"We know Porto is an outstanding club who nurture players in the best possible way and provide a brilliant football education."

The stats

Diaz's performances over the past three seasons for Porto combined with a coming-of-age Copa America last summer have seen his stock steadily rise.

He has netted 41 goals in 125 games in total for the Portuguese giants, including 14 in 18 league games this season, which makes him the Primeira Liga’s second-top scorer.

After a red card in the second game at the Copa America, he scored four times, including a spectacular overhead kick against Brazil which reportedly made Klopp sit up and take notice.

Fit right in

Diaz grew up in poverty and there were concerns he was malnourished, like many of Wayuu ethnicity are.

But the winger never let that get in the way of his development and that sort of determination has endeared himself to Klopp.

He plays on the left of a midfield four at Porto, so will not shirk his defensive duties even if they increase.

And his arrival will help the likes of Mohamad Salah, Sadio Mane, Diogo Jota and Roberto Firmino too.

Speaking in 2020, Diaz explained: "I’ve liked goals very much since I was little but if I see a team-mate in a better position, I try to assist them.

"Sometimes team-mates say to me, ‘Why don’t you shoot?’ — but I prefer to give the pass to them because they’re better placed to score a goal."

The Anfield faithful will hope they see plenty of that as they look to close the gap to Premier League leaders Manchester City.