Ahead of the Reds’ return to the Premier League, after 17 days away, there was much talk over how Klopp would set his side up, with the pick of a near full-strength squad.
It was a bold move to give Diaz his full debut, but it paid off as the £50 million signing produced an exciting display and went close to scoring on a number of occasions.
Given the language barrier and the lack of training time – less than a week after arriving from Porto – it came as a surprise to all, including Klopp, that Liverpool’s new No. 23 was able to slot straight in.
“That’s a surprise for me as well!” he told BT Sport.
“But that’s exactly how he’s looked in the training sessions, so I thought ‘OK, why shouldn’t we try it then?’, just without five million informations, just let him play.
“He watched us, obviously, and we showed him a lot of situations, but it looks natural in a lot of moments. That’s really quick.
“It was an outstanding game for the first start, it was really impressive.
“He was involved in so many good football moments and had his own finishes and all these kinds of things. So really, really good performance.”
The new-look duo combined well throughout, and also speaking to BT Sport, the left-back praised the added competition.
“My Spanish isn’t great, I don’t think his Scottish is quite up to scratch, but we made it work today!” Robertson said.
“Obviously, my partnership with Sadio over the last five years, it’s been special playing with him.
“He’ll come back full of confidence, winning a major trophy for his country. We’ve got options and that’s the most important thing.”
Robertson added on Diaz: “His first training session I saw him flying about and thought ‘he’ll be OK here’!
“We just need to let him bed in here, he’s still got obviously the language to hopefully pick up and the way we play.
“But I thought, for his first start, he was excellent today.
“I thought everyone was really important today, but him flying into tackles and stuff, that’s one way to get the crowd to love you straight away, and I think they really took to him.”