Ancelotti had been hoping the Brazil midfielder would be back for Saturday's must-win clash at Stamford Bridge following two and a half weeks on the sidelines. But the 24-year-old is yet to take part in full training with his team-mates.
Defender Alex, who has been out for the same length of time with a similar injury, did train on Wednesday and could come into contention for the weekend, while Ashley Cole also resumed training after missing out on Tuesday.
But Michael Essien joined Ramires on the sidelines after straining a knee ligament in Saturday's 3-0 win over West Ham.
Should both Essien and Ramires fail to make it, Yossi Benayoun could be handed his first Chelsea start for more than seven months.
Benayoun has made three substitute appearances since recovering from a serious Achilles injury, but the form of Essien, Frank Lampard and John Obi Mikel in recent weeks has meant the Israel captain has been forced to bide his time on the bench.
Ancelotti was also using training this week to try to forge a partnership between Fernando Torres and Didier Drogba, who have failed to strike up an understanding since the former's £50million move from Liverpool.
Torres' long-awaited first goal for Chelsea on Saturday convinced Ancelotti he must at least try to accommodate both players in his starting XI if possible.
Source: PA
Source: PA