Chelsea manager Jose Mourinho has expressed doubts over whether former midfielder Frank Lampard can ever return to Stamford Bridge.
The 36-year-old left the Blues at the end of the 2013-14 season after 13 years of service, with many thinking that he would be linking up with MLS club New York City FC.
However, Lampard went on to secure a contract with Manchester City - one of Chelsea's biggest rivals for the Premier League title - until the end of the season.
Mourinho is quoted by BBC Sport as saying: "We opened the door for [Lampard] to choose his future with us and we thought he was leaving to the States.
"We thought a couple of years later he would come back to do what he wants. First-team coach, assistant manager, ambassador. For Frank we would find a new department for him to run, to do what he wants.
"We were surprised by his decision to go to Man City but he was a free agent, he can do what he wants with his career and the last thing I would do is criticise his career. I don't know [if that door is now closed]. I don't know."
Chelsea are five points ahead of second-placed Manchester City at the top of the Premier League table.