Mata spent two-and-a-half seasons at Chelsea, winning the FA Cup, Champions League and Europa League.
And he was a fan favourite winning Chelsea’s Player of the Year back-to-back.
But the Spanish playmaker left Stamford Bridge in 2014 for United after struggling to secure a regular first-team place under Jose Mourinho.
On Friday, Chelsea sealed the title with two games to spare after a 1-0 win over West Brom.
And Mata still holds his former club in great regard and saying they deserved to win the league this season.
He said in his weekly blog: “I think it’s fair to congratulate Chelsea for winning the Premier League.
“They’ve been the most consistent team in the League and thanks to that they were able to celebrate the title last Friday after defeating West Brom, so my sincere congrats to them.”
