Arsenal hit with more injury woe
And the pair - who are both suffering with groin problems - could also miss Tuesday's Champions League semi-final second leg tie with Manchester United at the Emirates Stadium.
"For the weekend we have lost Eduardo certainly," said manager Arsene Wenger.
"He has done his groin again unfortunately. Rio Ferdinand fell on him when he had that accident. His knee went on his groin and that detached some fibres. Silvestre has a groin [problem] as well.
"We have not scanned them yet, so we don't know about Tuesday, but they both miss Saturday for sure."
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