World number one Alcaraz and sixth seed Rune teamed up at a tournament in France called Petits As when they were 14.
Six years on and the duo, now 20, will do battle on Centre Court for a place in the semi-finals.
“It’s great. It’s a good feeling. It shows that the young players are doing a great job. For me it’s cool. For him it’s also cool, I guess,” said Danish hot-shot Rune.
“To be able to play a quarter-final against a player that is the same age, at the top of the ranking, feels amazing. I’m really looking forward to that match. I even looked at it when I was in the first round.
“I couldn’t really afford to look at it because there were so many matches before this would eventually happen. Now we’re here so I’m really pumped and excited for it.”
Rune came through in four sets against Grigor Dimitrov while Spanish sensation Alcaraz passed his sternest test yet, beating former finalist Matteo Berrettini in four.
“Carlos had a big forehand also in juniors,” added Rune. “I think he’s the same, just so much better now. I think back then he was Carlos, and now he’s Carlos. He’s the same, just improved very, very a lot and very quickly.
“We played doubles one time in Petits As. Hopefully we can do it again, but now we’re going to battle against each other.
“It was good, because he’s amazing. Also, the more shots he could hit the better. We played good together. I think we made the semi-final.
“For sure I would like to play doubles with him again. I know he doesn’t play a lot of doubles, me too. But maybe one day we can have a chance to play.”
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