Raonic retires to put De Minaur through at Australian Open
The 33-year-old was clearly in pain, seemingly with a hip problem, and called it a day while losing 6-7(6), 6-3, 2-0 on Rod Laver Arena.
"First of all I hope Milos has a speedy recovery," said the 10th-seeded Australian, who beat Novak Djokovic at the lead-up United Cup.
"It's not great to see him like this. He deserves to be healthy and playing the incredible tennis that he has done for so many years."
Raonic, who made the semi-finals in 2016, has long been plagued by injuries and was inactive on the tour for nearly two years from July 2021 to June 2023.
He took a medical time-out while leading 5-4 in the first set before returning, but ultimately he could not go on.
"It's no secret I have started the year pretty well," said De Minaur as he looked ahead to a next-round clash with unseeded Italian Matteo Arnaldi.
"Now it's all about keeping my head down and keeping doing the same things."
