Liverpool manager Jurgen Klopp is still laughing off the idea his side could win a historic quadruple of trophies, but he does concede he has the best squad during his tenure at Anfield.

One of the reasons for that bold statement is the recent arrival of Colombian winger Luis Diaz, who has boosted the German’s attacking options for the second half of the season.

The Reds ended a 10-year wait to win a domestic cup competition last week, beating Chelsea on penalties to win the League Cup.

They are heavy favourites to reach the quarter-finals of the Champions League on Tuesday — 2-0 up against Inter Milan after the first leg of their last-16 tie — while a heavily rotated team cruised into the FA Cup quarter-finals with ease.

A seven-game winning streak in the Premier League has also rekindled the Premier League title race with Manchester City, which seemed lost at the turn of the year.

January could have wrecked Liverpool’s season, with Egypt’s Mohamed Salah and Senegal’s Sadio Mane heading off to the Africa Cup of Nations, where Senegal beat Egypt on penalties in the final.

But Diaz arrived from Porto towards the end of the transfer window for a fee that could rise to £50 million ($66 million), refreshing Klopp’s attacking options as he mounts a four-pronged challenge.

Triumvirate

Much of the success of the Klopp era has been dependent on attacking triumvirate of Salah, Mane and Brazil forward Roberto Firmino.

But all three are out of contract at the end of next season, at which point they will all be beyond 30.

“It was necessary, we cannot rely on these boys,” said Klopp after Diaz starred in Saturday’s 1-0 win over West Ham.

“You need to bring in quality and fresh energy. That’s what we tried and it looks like it worked out.”

Klopp could afford the luxury of leaving 17-goal Diogo Jota on the bench at the weekend, while Salah was replaced with the game still in the balance to give him a rare rest before Inter’s visit.

In the San Siro three weeks ago, it was Diaz’s introduction that helped turn the tide as Klopp made four changes before the hour mark.

Inter were the better side for much of the first 75 minutes, but the financial gulf between the top of the Premier League and Serie A showed in the final stages.

The Italian champions, who were forced to sell Romelu Lukaku and Achraf Hakimi last year due to finanical problems, faded in the final stages when Firmino and Salah scored to give the tie a one-sided look heading back to Merseyside.

“The boys have now really proper quality in depth, but we cannot play all competitions and go far in the competitions if we don’t have this depth — there is no chance,” said Klopp.

“You can do it for a year when you are lucky with injuries, but I think we had years where Bobby, Sadio and Mo played pretty much all the games.”

Diaz, 25, has scored just once in eight appearances for Liverpool, but he has been on the winning side in all of them as his direct running with the ball and pressing off it have fitted seamlessly into Liverpool’s style.

Even players who have gone on to enjoy huge success at Anfield such as Andy Robertson and Fabinho have initially been given months to settle and meet Klopp’s demands..

“When we saw him play for Porto we thought that is exactly what we want him to do as well,” said Klopp. “He looks like a Liverpool player.”