Hilario will deputise for Petr Cech in Chelsea's goal after the Czech Republic goalkeeper tore a calf muscle against Inter Milan in midweek.
Ashley Cole is a long-term absentee with a broken ankle and Yury Zhirkov has a calf injury. Paulo Ferreira is back in contention after not being registered for the Champions League in midweek but Florent Malouda is expected to continue at left-back.
Jose Bosingwa, Michael Essien and Deco (all knee) all remain sidelined.
Carlo Ancelotti insists John Terry will not let his shattered relationship with Wayne Bridge affect his performance.
All the focus has been on whether the two would shake hands before the match following allegations Terry had an affair with his former team-mate's ex-girlfriend.
But Chelsea manager Ancelotti said: "John Terry is professional and doesn't have a problem in staying focused on the match.
"He has been doing good performances. He is in focus and has a good mentality.
"He has had a fantastic season and will do the same until the end of the season."
Carlos Tevez is set to return to the Manchester City starting line-up.
Tevez has missed three matches after returning to Argentina following the premature birth of his baby daughter.
But with Emmanuel Adebayor suspended for four games, Tevez seems sure to feature. Kolo Toure and Roque Santa Cruz (both knee) are doubts.
With thoughts of a trophy gone for another year after the midwek FA Cup exit at Stoke, City are now focussed on fourth spot.
But as they still have to face Tottenham, Aston Villa, Arsenal and Manchester United during a testing run-in, in addition to Chelsea, it will be tough to scramble up from their current fifth place.
However, after his time in Italy, it seems Mancini is impervious to pressure.
"I don't feel pressure," he said.
"I worked at Inter for four years. After that it is impossible for me to feel pressure.
"I am disappointed because I wanted to win a trophy this season.
"But now my focus is on fourth position - and we still have a good chance."
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