The Blues set up a Champions League semi-final meeting with Atletico Madrid after Demba Ba netted a 87th-minute strike to seal an aggregate win against Paris Saint-Germain at Stamford Bridge on Tuesday.
I believe they are recovering step-by-step and on Sunday they should be in conditions to play another difficult game
And Mourinho, whose side are in second place and two points behind leaders Liverpool, is optimistic that his Blues squad will be fully recovered for the game in Wales.
“There is a lot of happiness but at the same time a lot of fatigue (after the win over PSG),” Mourinho told his pre-match media conference.
“It was not easy physically or mentally but obviously when you are happy it looks like things are easier.
“I believe they are recovering step-by-step and on Sunday they should be in conditions to play another difficult game.”
Mourinho warned Chelsea that Swansea will pose a difficult challenge as the Blues aim to keep pace with their title rivals.
“They are a good team and they play good football,” added Mourinho.
“Especially at Swansea it is never easy and Chelsea knows that better than other teams.
“They still need the three points. They are not in big danger like other teams but they still need a couple of points to stay in the Premier League and of course they will try to get points out of this game.”
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