Current first-choice Kalac is travelling to London but has a dislocated finger and the club are pessimistic about his chances.
Kalac suffered the injury in training on Sunday while his back-up Dida was incapacitated during Saturday game against Palermo without even stepping on the pitch - the Brazilian hurt his back while sitting on the bench.
"I don't think Kalac will make it. For a goalkeeper a finger is very important but we will see after training this evening. If he can't train, Fiori will play," Ancelotti said.