Don't stumble.

On the way to the longed-for title quadruple, FC Liverpool are clearly the favorites against Bayern-Schreck FC Villarreal, but Jürgen Klopp urgently warns against the "King of the Cups".

"Villarreal has perhaps the most successful coach in cup competitions.

It's incredible what he's doing.

Anyone who throws out Juventus and Bayern deserves to be in the semi-finals," said Klopp before the semi-final first leg in the Champions League against the Spaniards on Wednesday (9 p.m. in the FAZ live ticker for the Champions League and on DAZN) at Anfield.

This refers to Unai Emery, the shrewd Villarreal coach who has won 84 per cent of his knockout duels in the premier league and Europa League since the 2009/10 season.

Only former Real Madrid coach Zinedine Zidane is slightly better with a rate of 88 percent.

Klopp and his Reds have experienced this painfully themselves.

When the former Dortmund master coach reached for the first title with Liverpool in the Europa League final in 2016, Emery had something against it with Sevilla FC.

The coach has won the competition four times, last year with Villarreal against Manchester United.

But now it's top class, and Klopp evaluates the task as "hard, hard, hard".

Klopp was impressed by the defensive skills of the seventh-placed Primera Division team in the 1-1 draw in Munich in the second leg of the quarter-finals.

"It's going to be difficult, but it's the semi-finals in the Champions League.

If it weren't difficult, something would go wrong.” Bayern underestimated Villarreal and experienced a nasty surprise in the first leg when they were still lucky to be 1-0 down.

Contracts with Salah and Mané in focus

Klopp doesn't want to make this mistake.

Because it beckons a year for the history books.

For the first time in the club's history, the LFC could win all four titles.

They've already won the League Cup, they've reached the FA Cup final against Chelsea and Thomas Tuchel, and Liverpool are just a point behind long-time rivals Manchester City in the league.

The hunger for titles is correspondingly large.

"I want to relive the feeling we had after winning the Champions League," says striker Mohamed Salah, looking back at the 2019 title coup and thinking back to the "incredible" winner's parade through the city.

With eight goals in ten games, the Egyptian is also Liverpool's top scorer, just like in the league (22 goals).

No wonder Klopp would rather extend Salah's contract, which expires in 2023, today rather than tomorrow.

The contract with Salah's team partner Sadio Mané also expires in a year.

There is currently not much time for contract talks.

They travel to resurgent Premier League rivals Newcastle United on Saturday and the return leg at Villarreal on Tuesday.

"It's brutal, but the best situation you can have," said Klopp.

Until the Champions League final on May 28, there are almost exclusively English weeks, but the Reds would not want to miss the last date.