Jack Draper beat Andy Murray 7-6 (8-6) 6-2 in their first competitive meeting to reach the fourth round of the Indian Wells Masters.
The 21-year-old will now play US Open champion Carlos Alcaraz on Tuesday.
Draper was on Centre Court as an 11-year-old when Murray won Wimbledon for the first time in 2013 and has formed a strong bond with the Scot.
“If I was going to say one sporting person who has inspired me the most it would be Andy,” Draper told BBC Sport.
“To come off court with the win against Andy – I’ll never forget that moment.”
Draper broke for a 2-1 lead in the first set after Murray double-faulted, and had a chance to serve out the set at 5-4. But Murray broke back to love, and Draper then had to serve an ace to fend off a set point at 5-6.
The tie-break was as close as the set until a fine backhand service return and then an ace secured it for Draper after 83 minutes by eight points to six.
Draper had his upper right leg tightly strapped before the second set began, and it was only after he had broken for a 4-2 lead that there were occasional signs it was affecting his movement.
But Murray was tiring, too, and Draper was still able to save two break points to extend his lead.
After having the strapping removed at the change of ends, the Englishman completed victory as Murray hit a fifth double fault on match point.
“I’m very proud of myself. Beating Dan Evans, as well [in the previous round]. Dan’s a fierce competitor, someone who I’ve looked up to. That gave me confidence to go out there tonight and think even though it’s a really tough mental challenge again, I can do this,” Draper said.
“This is my first tournament in the last couple of months since I played Rafa [Nadal] in the Australian Open.
“My body is in a position at the moment where I am improving a lot. I have a fitness trainer, Dejan Vojnovic, who is incredible but I have only been working with him for three months and this is a long-term project.”
Draper missed two recent tournaments in the Middle East because of soreness in his right hip and the problem has not entirely gone away.
“It’s something that is bothering me a bit at the moment, but day by day it can only get better but being sore in this tournament was always something that was going to be likely,” he said.
Murray will now move on to Miami, where he is a two-time champion, with at least a week to rest before his first-round match.
“In the tie-break, I had a few opportunities but he came up with a really good return on the six-all point and then the second set was tough for me, physically,” Murray said.
“Just a bit of fatigue to be honest – recently I’ve played quite a lot of long matches and the first set was very tough physically for both of us, and here it’s not that easy to finish points.”