Arsenal defender William Gallas will miss the rest of the season with a knee injury sustained in the Gunners' 1-1 Champions League draw at Villarreal.
The 31-year-old damaged the medial ligament in his right knee during a collision with striker Giuseppe Rossi.
Goalkeeper Manuel Almunia has been ruled out for three weeks after he injured his right ankle.
Arsenal boss Arsene Wenger has also lost Gael Clichy with a back injury that will keep him out for two weeks.
Strikers Robin van Persie and Eduardo (both groin) will undergo fitness tests on Friday before Saturday's Premier League match at Wigan.
In Gallas's absence, Wenger is likely to call upon Johan Djourou as Kolo Toure's partner in the centre of Arsenal's defence.
Mikael Silvestre is also available after injury, while Alexandre Song has filled in at centre-half in the past.
Gallas stayed on the field for several minutes after the challenge with Rossi before limping off and being replaced by Djourou in the 43rd minute.
Almunia was replaced by Lukasz Fabianski after 28 minutes at El Madrigal, also following a clash with Rossi.
And Wenger is pessimistic about his first-choice goalkeeper's chances of recovering for next Wednesday's second-leg encounter at the Emirates Stadium.
"Manuel is a recurrence of an ankle injury, which probably will be a couple of weeks," said Wenger.
BBC SPORT