Daria Abramowicz, who is in Paris to assist the 19-year-old Swiatek at the French Open which starts on Sunday, told Reuters that the demands on players affect their mental health and well-being.
"I absolutely understand the (Osaka's) decision in terms of when a player loses a match, and tennis is such a specific sport because at the end of the tournament only one person does not lose," Abramowicz said.
World number one Ash Barty on Wednesday withdrew from the March 1-6 tournament in Doha with a left leg injury, while world number three Simona Halep and 2019 US Open winner Bianca Andreescu are also skipping the event.
"I don't want to have injury or anything. I want my body to rest properly." Swiatek is also scheduled to compete in the Dubai Duty Free Tennis Championships next month.
I didn't see like a lot of people around, because at that time we had many restrictions and it was impossible to get like big gatherings.
Swiatek, who is ranked 18th, had earlier said she was finding it tough to deal with the weight of expectation at the Australian Open following her Roland Garros triumph.