Andy Robertson admits he knew Luis Diaz was going to make the grade at Liverpool after his first training session.
The Colombian joined up with the Reds squad last week after completing his £50m move from Porto.
Liverpool swooped in and signed the winger ahead of Tottenham and he made his first appearances in Sunday's FA Cup win over Cardiff City.
Diaz was then handed his first start in Thursday night's win over Leicester City.
He teamed up with Robertson down the left flank with Sadio Mane still absent and the Scot was full of praise for his new teammate.
"His first training session I saw him flying about and I thought 'he'll be okay here'," Robertson said on BT Sport.
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"Look, we need to let him bed in, he's obviously still got the language to pick up and the way we play and everything.
"I thought for his first start he was excellent today. Him flying in to tackles today - that's one way to get the crowd to love you straightaway and I think they really took to him."
Diaz will add competition to Liverpool's forward line.
Robertson is confident that such strength in depth will push on each and every individual with the Reds still eyeing a unique quadruple.
"We (him and Diaz) made it work today. Obviously my partnership with Sadio over the past five years has been special," added the left-back.
"He'll come back full of confidence winning a major trophy, and we've got options to bring off the bench. You saw tonight a real strong bench.
"We've got competition all over the park. It'll keep pushing each other, it'll keep putting pressure on each other and hopefully the results will keep coming."
Klopp concedes he has been impressed with the speed in which Diaz has settled in on Merseyside.
He echoed Robertson's comments on the winger's early training efforts, which gave him the confidence to throw him in so early.
The German said: "It is a surprise for me as well, but that is exactly what he looked like in our training sessions. We thought we we'd try it.
"Without five million formations, we just let him play. It was an outstanding game for his 1st start, really impressive."
He also added on Diogo Jota's two-goal performance: "The second goal is a brilliant goal. A counter-press. I love it. Jota with a little genius moment to put it into the right spot.
"The first goal is really when you are in a goal-scoring moment then you are there. He is in that. Really happy for him and for us."
