Mourinho claimed he would concede the Premier League title to Liverpool by fielding a weakened side when the two teams face each other on Sunday.
A win for Chelsea would still leave them two points behind Brendan Rodgers' men, whereas they go into the semi-final second leg against Atletico Madrid as favourites to make the final.
The Chelsea manager has accepted that the Premier League is out of reach for this season and winning on Sunday would only help Manchester City's chances, not theirs.
Now the board at Stamford Bridge has given their consent for Mourinho to field whatever team he feels necessary, even if it means absorbing a heavy defeat.
It means that Mark Schwarzer could be rested to make way for third choice goalkeeper Henrique Hilario while chances could be given to under-21 stars Tomas Kalas, Nathan Ake and Andreas Christensen.
Manchester City is obviously very keen to see Chelsea win on Sunday as a win would put the title back within their reach. They are six points behind Liverpool but have a game in hand as well as a superior goal difference.
However, the Premier League has confirmed that Mourinho is entitled to play any team he desires.
Mick McCarthy and Ian Holloway have been fined for fielding weakened teams in the past but a movement, started by the latter of the aforementioned pair, forced the Premier League to change their policy on such matters.