The Dutchman was signed by Louis van Gaal from Ajax for a fee of £13.8m and spent four seasons at the club, making 141 appearances in total.
He played an important role in Man United’s Europa League success under Mourinho but spent last season on the fringes, moving back to Ajax earlier this summer.
Speaking in an interview earlier this week, Blind stressed that his relationship with Mourinho had always been a good one.
“I almost played 150 matches. I won four trophies,” he said. “I had a very beautiful time. I had many nice moments there.
“I am very grateful to the fans. I worked very nice[ly] with Mourinho.”
Mourinho cut Blind out of the loop soon after he, along with Matteo Darmian, produced a sluggish display in a defeat to FC Basel in November. He had, up to that point, made ten appearances, including starting United’s opening three Premier League games. He would only make six more in almost as many months.
He was a disciplined and versatile servant to the club, generally unremarkable but more or less always tidy, and moved on at the right time.