Casillas is out with a broken hand, although he was dropped by Mourinho before the injury, with speculation suggesting there is a major feud between the pair.
“I cannot say that a player will hold [on to a position] until the end of the season,” said Mourinho.
“But I will say that again Diego Lopez has played a big game and helped the team get a result.
“In football, we have to try and be honest with yourself and with your players.
“Along that line, it will be hard for Diego to come out of goal.”
