But the ankle has healed, and even if preparation for this particular Grand Slam has been a little thin, the optimism has returned, too.
A core team is gradually taking shape. Sebastian Sachs is in position as the coach, Jez Green’s strength and conditioning expertise is bearing fruit, and physio Will Herbert is an increasingly frequent presence on tour.
Raducanu’s run of coaches has been well documented, but the word over the past few months is that she really is very keen to develop a long-term partnership with one of them.
Dmitry Tursunov decided in October he was not that man, warning – in an interview with tennismajors.com – that Raducanu was consulting too wide a range of voices.
“I think that the way I’ve been brought up, I’ve always had quite a lot of people around me and it’s more just been me picking and choosing what I want to take and what I want to leave,” the British number one told BBC Sport in response to the Russian’s comments.
“I think a part of it was also I didn’t have that core, small team. I didn’t have that solid set-up and the team that I really fully trusted.
“So for me this year, now I feel like I’ve definitely got that more so, and I don’t probably need to consult as widely any more.”
Sachs is young, at 30, and having had a brief career as a player on the Futures Tour, can also double as a very handy hitting partner.
A calm and attentive man, he has already worked in a coaching capacity with Victoria Azarenka, Julia Gorges and then Belinda Bencic, who became a top-10 player and an Olympic champion under his watch.
“We kind of build off each other’s ideas, and he’s just a really good person to have in the team as well,” Raducanu said. “I think that’s been going really well so far and I really want to carry on and for it to last.”
Herbert’s healing hands will have been invaluable over the past week with so little time to restore that ankle back to full health.
He also delivers Raducanu’s fitness programme when Green is not available.
The strength and conditioning coach started working with the 20-year-old at the end of last year, and designs a programme for Herbert to deliver when he is elsewhere.
Green, who was such an instrumental part of Andy Murray’s success, has been working primarily for Dominic Thiem and is not in Australia this year.
But the expectation is that he will also be able to do a number of weeks with Raducanu. A plan for the year is likely to emerge after the Australian Open.
Raducanu’s fortunes improved in the second half of last season. She won eight of the 15 matches she played since Wimbledon, and reached the semi-finals in Seoul. But then came a wrist injury which curtailed her season and prevented her doing any meaningful work on court before the start of December.
“You can tell she’s a lot stronger than she was this time last year,” the former British number one Laura Robson told BBC Radio 5 Live this week.
“The improvements I have seen over the last couple of days with the ankle have looked really promising, but you never know if it’s going to be enough, if the turn around is too quick and you’re thinking about the ankle rather than the tennis.
“You’ve got to think long term. She has done all this work in the off season – if it’s too soon to come out on Monday, then it’s OK.”