The 28-year-old defender completed a move back to the Amsterdam club this week after he struggled to hold down a regular spot in the first team at Old Trafford under Mourinho last term.
Blind joined Manchester United from Ajax back in 2014 but has now returned to the Dutch club for a transfer fee believed to be worth around £18.1m.
Now, Mourinho has paid tribute to Blind after his move to Ajax from Manchester United was confirmed this week.
Mourinho is quoted as saying by Metro: “I would like to say a big thank you to Daley Blind for everything he has done for the club since he joined in 2014.
“I have to say, that in my 18 years of management, Daley is one of the most professional players, both on and off the pitch, that I have had the pleasure to work with.
“I would like to take this opportunity to wish him all the very best as he re-joins his boyhood club, Ajax, and thank him from the bottom of my heart for his commitment and dedication over the past two seasons.”
Manchester United have made three signings so far this summer after having brought in Diogo Dalot, Fred and Lee Grant.
Mourinho will be looking to steer Manchester United to a Premier League title challenge next season after the Red Devils finished in second place in the table last term and without a trophy.
The Red Devils ended up 19 points behind Manchester City last term and they are now aiming to win the Premier League title for the first time since their final triumph under Sir Alex Ferguson back in 2013.
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