Courtois, 22, has earned a reputation as one of the world’s best young shot-stoppers during his loan spells at Atletico Madrid before returning this summer to challenge Cech, 32, for his Stamford Bridge place.
And Mourinho admits that the competition between the pair is a “great situation” for Chelsea heading into the new Premier League campaign.
“I don’t tell you [who is first choice] because they don’t know and the team doesn’t know,” said Mourinho, whose side take on Burnley in their Premier League opener on Monday. “They will know at the same time, all of them.
Is it a problem for me? A great problem, because they are both fantastic goalkeepers
“In my opinion, with all respect to fantastic goalkeepers around the world, I think Chelsea has two of the three best goalkeepers in the world – and this is something unique.
“Is it a problem for me? A great problem, because they are both fantastic goalkeepers. [But] I think it’s a problem that every manager in every club would like to have.
“For me, it’s not easy because I don’t think any manager is happy to see one player not in a very happy and comfortable situation. I’m not happy when other people are not very happy.
“It’s a difficult situation but for Chelsea Football Club it’s a great situation. The only thing I can say is that in this moment they are working hard and we are so happy to have them both.”
Asked if he would consider selling one of the two goalkeepers should either of them seek a move away, Mourinho added: “In this moment I don’t want to think about it because there is no offer and no possibility.
“I told them as a group today that every one of my players in the squad I’m happy to have them. I’m not waiting for anything and it’s not good to analyse something that is not on the table.”
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