In 2017, Manchester United played a Europa League match against Anderlecht, where Zlatan Ibrahimovic suffered a serious knee injury that could have been the end of his career.
But instead, the Swede traveled to Pittsburgh in the United States, where he was operated on by surgeon Freddie Fu, a specialist in cruciate ligament injuries who treated many sports stars.
The operation was successful - and barely seven months later Ibrahimovic made a sensational comeback.
- He's one of the top athletes I've ever touched.
He has many years left at the top, Fu said afterwards.
On Friday, the University of Pittsburgh, where Fu worked, announced that the 70-year-old had died.
According to the Pittsburgh Post-Gazette, he suffered from cancer.
On Saturday night, Zlatan Ibrahimovic posted a picture on Instagram where he expresses his grief after the star doctor's death.
Freddie Fu gave me a second chance in my career.
I'm still on top because of him.
I owe him everything.
Thanks Freddie Fu.
Rest in peace".