The physio was initially called after she walked gingerly to her chair following the slip which happened at the back of the court as she changed direction mid-point but she was able to continue without medical attention.

She was 4-1 down in the tie-break at the time but came back to take the set after Boulter had double-faulted on set point at 10-9. It was one of three set points the defending champion wasted although it took Raducanu six attempts to nail one of hers.

There was nothing in it as a contest with the 79-minute set going with serve up until the tie-break. Raducanu put Boulter under intense pressure on her serve in the fifth game but the 27-year-old saved four break points to hold. Raducanu then saved two in the next game on her serve, serving out with a cry of satisfaction and a clenched fist.

Taking the tie-break sets Raducanu up with an inviting opportunity to set up a shot at what would be her first WTA title but it would be unwise to write Boulter off. She has plenty of motivations, one of which is to prove the point that she really is the true British No 1.

Another is the chance of a repeat of the romantic double she and boyfriend Alex de Minaur pulled off in March when they won titles on the same weekend, Boulter at the San Diego Open – her first WTA500 event – and De Minaur at the Mexican Open. The Australian, who Boulter watched during the rain delay, is through to the final of the Libema Open in Holland.

It was only the second meeting of Raducanu and Boulter’s careers with the previous one coming in India in 2019 when Raducanu, a set down at the Solapur tournament, pulled out through injury. If that has been the story of her career either side of the extraordinary win at the 2021 US Open then Nottingham has shown what a fit Raducanu can deliver. She has looked impressive, both in the vigour of her groundstrokes and her movement around the court.