The veteran midfielder raised eyebrows when he decided to join Chelsea’s Premier League rivals City after leaving the west London club as a free agent at the end of last season.
Lampard ‘signed’ a pre-contract agreement with MLS side New York City FC but with the new season not starting until March, the midfielder joined their sister club City.
The 36-year-old was expected to leave City at the end of last year to join up with the MLS side but instead agreed a new deal to keep him at Etihad Stadium until the end of 2014-15 campaign.
Mourinho hinted that Chelsea did not expect their all-time record goal-scorer to move to Manchester City and insisted that he would love to see Lampard back at the club in some capacity in the future.
Speaking on Sky Sports’ Goals on Sunday, Mourinho said: “We let him go for different reasons.
“First of all, I think the motivation Frank has to have this role at City wouldn’t be the same motivation he has to have the same role at Chelsea.
“Secondly, we open the door for him to choose his future and we thought he’d go to the States and would come back after a couple of years to do what he wants.
“We would have found a new department for him! What he did for Chelsea for more than one decade was something amazing.”
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