Emma Raducanu dropped to the ground of Court One in disbelief as the 18-year-old Briton, who only a couple of months ago took her school leaving exams, reached the fourth round of Wimbledon on Saturday.

The Canada-born Raducanu, ranked 338 in the world, only made her debut on the WTA Tour in June but outclassed the vastly-experienced 45th-ranked Sorana Cirstea 6-3, 7-5.

Emblematic of her coolness was how she hit back from 3-1 down in the first set to rattle off eight games in a row and take control of the match.

"I am so speechless," said Raducanu. "At the end I did not know what my reaction would be and I just dropped to the floor.

"I was nervous beforehand as this is definitely by far the biggest court I have played on.

"It was a tight match and when I was 3-1 down I tried to hold my nerve and managed to get back into the game."

Raducanu, who moved to England aged two with her Romanian father and Chinese mother, will next play feisty Australian Ajla Tomljanovic.

Raducanu had said on Thursday after reaching the third round she would place a spot in the fourth round of Wimbledon above top grades in her A level exams (Maths and Economics).

She had added that would be news to her parents as was the case when they saw her packing for Wimbledon. 

"When I was packing for Wimbledon to come into the bubble my parents said are you not packing a bit too much match kit?" she said.

"Mind you I think I may be calling on the hotel laundry service before Monday to launder it." 

Cirstea perhaps will regret her remark prior to the match that her opponent "was a very sweet young girl" for there was nothing of that in Raducanu as she went for the jugular once she hit her stride. 

However, it was a range of sublime shots from the teenager, not brute strength, that saw her pin Cirstea against the ropes.

She secured the first set with a delightful lob but more often than not it was a striking whipped forehand cross court that flummoxed Cirstea.

Raducanu's idol and Cirstea's compatriot Simona Halep would have been proud of the youngster's diverse array of strokeplay.

Cirstea did rally when she came from 0-40 on her serve and on the brink of going 4-0 down to win the game and then broke back.

There was still time for the game of the engrossing match on Cirstea's next service game which went on for almost 15 minutes and saw the 31-year-old Romanian save five break points. 

Nevertheless despite the renewed fight form Cirstea it did not nudge the irrepressible Raducanu off course and she went on to a deserved victory and soaking up the adulation of the crowd.