Chelsea playmaker Cesc Fabregas is likely to be back for the home game with Everton in the Premier League in midweek after missing two matches with a hamstring problem.
"We didn't want to risk two players at the same time. We risked Willian and to start two players with a risk is a big gamble," added Mourinho in reference to the 2-1 victory over Aston Villa at the weekend.
Fabregas's expected return will present the manager with something of a dilemma because Brazilian Ramires has excelled as his midfield deputy after a season plagued by injury.
"The best Ramires is back and the best Ramires played against Liverpool, Manchester City and Aston Villa," said Mourinho.
"He is a different profile of player but a fantastic player for us."
Ramires came on when Fabregas limped off midway through Chelsea's League Cup semi-final second leg victory over Liverpool at Stamford Bridge two weeks ago.
The Londoners sprinted seven points clear at the top of the league after defender Branislav Ivanovic grabbed the second-half winner with a ferocious shot at Villa.
"Every striker in the world would be proud to score that magnificent goal," said Mourinho.
"For a right back whose left foot is not his best it is an amazing goal.
"He is a great guy and what he is doing for us is unbelievable with the foot injury he had against Liverpool when he still played the rest of the game, and he also played against City and Villa.
"He is one of the best signings. He came immediately after I left Chelsea and after that he made a fantastic contribution for this club."
Serbian international Ivanovic, who can also play in central defence, joined Chelsea from Lokomotiv Moscow in 2008, just after Mourinho's first spell at the club ended.
Image: Cesc Fabregas of Chelsea in action
Photograph: Richard Heathcote/Getty Images
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