Liverpool manager Jurgen Klopp warned against making early judgments on signings for next season after Roberto Firmino's improvement at Anfield.

Firmino was a £29million signing from Hoffenheim in the off-season and made a slow start to his time at Liverpool.

However, the Brazil international's goal against Watford in the Premier League on Sunday took his tally to 11 in all competitions this campaign.

Klopp said the 24-year-old's progression was another illustration of a signing being judged too quickly.

"It wasn't a surprise to me when I heard people questioning him. That's how it is in Germany too," the former Borussia Dortmund coach told the Liverpool Echo.

"You don't watch too much German football. You get a player from Hoffenheim in Germany and everyone thought, 'Oh, a nice signing Liverpool’.

"But not many people here knew him because he wasn't from Bayern [Munich], he wasn't from Dortmund.

"I knew about Roberto. When I heard that Liverpool had signed him I thought, 'how have they done this?'

"Now with Roberto you can see the confidence in his work. All the players are more confident than before because they've had more time working together."

Klopp added: "What we can learn from Roberto's situation going forward when it comes to next season's signings is wait to make judgements. Don't be too quick to judge players."

Liverpool are preparing to host Chelsea on Wednesday ahead of a trip to West Brom and the Europa League final against Sevilla.