Raducanu was clutching her back when she took a medical timeout after going 5-2 down but returned to the court minutes later where the Canadian held to love to take the opening set.
The 19-year-old has had mixed results after winning her maiden Grand Slam title at last year’s US Open but has had an encouraging run in the clay court season where she reached the quarter-finals in Stuttgart and last 16 in Madrid – the latter tournament also seeing her struggle with a back issue.
Djokovic and Brit Norrie advance in men’s draw
Raducanu, who is currently without a full-time coach following her split from Torben Beltz last month, will be hoping to return to full fitness by the time the French Open gets under way at Roland Garros in less than a fortnight’s time.
The 2021 US Open winner and world number 12 was losing 6-2 2-1 when she withdrew in 2019 versus the Canadian, another previous US Open winner who has struggled with injuries throughout her career.
Raducanu held serve at the start of the second set but looked uncomfortable yet again and this time she took the decision to retire when she was down 2-1 in the second, telling a physio: “I can’t move.”
In the men’s draw, Novak Djokovic kicked off his quest for a sixth Italian Open title and the defence of his world number one ranking with a 6-3 6-2 victory over Aslan Karatsev in the second round.
Djokovic needs to reach the semi-finals to remain world number one, having missed several tournaments due to his coronavirus vaccination status. If not, he will lose top spot in the rankings to Russian Daniil Medvedev for a second time this year.
It was a fairly clean performance from Djokovic, who had only 10 unforced errors to Karatsev’s 36, as he continues his quest for a first title of 2022. The 20-time Grand Slam winner will face either three-time champion Stan Wawrinka or compatriot Laslo Djere in the next round.
Elsewhere, there was also a straight-forward win for British number one, and ninth seed, Cameron Norrie, who beat wildcard Luca Nardi 6-4 6-4 to set up a third-round clash with Marin Cilic.