Raducanu, 21, again showcased some of her best tennis in a 6-2 6-3 win under the Centre Court roof.
“Today was really up there with the most fun I’ve had on a tennis court,” said Raducanu, who beat Sakkari in the semi-finals of her incredible 2021 US Open win.
“I was telling myself, ‘how many times in your life are you going to play in front of a full Centre Court?'”, according to the BBC Sport.
Given a wildcard to play after plummeting outside of the world’s top 100 following injury, she has not lost a set in the first week of the Championships.
Raducanu, who has matched her career-best run to the fourth round in 2021, has dropped just 11 games since coming through a tie-break in her opening match.
She is the first Briton through to the last 16 of this year’s Wimbledon singles, with Sonay Kartal earlier losing to American second seed Coco Gauff on a wet Friday at the All England Club.
Kartal, the first British qualifier to reach the women’s third round at Wimbledon since 1997, was beaten 6-4 6-0 under the roof on Court One.
Next in Raducanu’s path is 123rd-ranked Lulu Sun, a qualifier from New Zealand who had never won a main-draw Grand Slam match until this week.