The 19-year-old has been under an intense spotlight since her fairytale triumph in New York 12 months ago and that will ratchet up a few more notches as she defends her title.
There have undoubtedly been more downs than ups since she lifted the trophy on Arthur Ashe Stadium, with niggling injuries disrupting her schedule and wins hard to come by.
But there are signs that perhaps Raducanu is getting to grips with the demands of the tour and last week at the Western and Southern Open was one of her best tournaments since here last year.
Navratilova told the PA news agency: “She played well in Cincinnati. It was massive because, if she hadn’t won the US Open and she has the year that she’s had, she’d be pretty happy about it and the British press would be happy about it.
“She’s up and coming and rising in the ranks. But, because she won the US Open the expectations went so high, and we saw how well she can play – it’s not even about the results, it’s why aren’t you playing anywhere near the level you played at the US Open?
It was amazing what she did. She's paying the price for it but I hope she can put it together because she's definitely a huge talent
Martina Navratilova on Emma Raducanu
“She couldn’t answer it but she started showing those signs in Cincinnati so she’ll be very relieved I think with how she played and let’s see how deep she can go.
“Once you win a big one you’re a scalp for everybody to beat, people play better, a little extra oomph in their step and you’re looking over your shoulder. And then also they learn how to play you.
“It was amazing what she did. She’s paying the price for it but I hope she can put it together because she’s definitely a huge talent.”
Raducanu’s victory was one of the most unlikely tennis achievements of all time but she is far from the only unexpected winner of a grand slam on the women’s side in the last five years.
— US Open Tennis (@usopen) August 27, 2022
Fifteen different players have won slam titles since the beginning of 2017 and so far eight of those are one-time champions.
Sloane Stephens was ranked 83rd in the world and on the comeback trail after foot surgery when she won her only slam title at Flushing Meadows in 2017.
The American’s career has been marked by inconsistency but she built on her success with a strong 2018 season, including reaching the quarter-finals again in New York.
Stephens admitted she did not enjoy the experience of defending the title but would advise Raducanu not to overthink it.
“I was happy when it was over,” Stephens told PA. “I thought it was going to be terrible and I was going to be miserable but it wasn’t. It was just stressful and overwhelming being a defending champion at a grand slam.
“But I had a good result, I made quarter-finals again. Obviously it’s always stressful being in New York and playing the US Open, especially defending a title, pretty extreme.
“It happens, it comes and goes and in two weeks’ time life will be back to what it is. I wouldn’t stress too much about it for her, there’s a lot of tennis left to be played in her career, she will be able to play and improve and regain those points.”
Raducanu, who could drop well outside the top 50 if she does not go deep in the tournament, will begin her campaign on Tuesday against France’s Alize Cornet.