Arsenal striker Eduardo has been ruled out of Sunday's Premier League clash with Chelsea at Stamford Bridge.
The Croatia international has failed to recover from the hamstring injury he sustained in the goalless draw with Aston Villa last week.
Midfielder Abou Diaby could return from the calf problem that has kept him sidelined since mid January as the Gunners attempt to nudge their title challenge back on track.
"Diaby is not yet back in normal training," Wenger told ArsenalTV Online.
"He progresses very well but we will still have to wait until Saturday. He is a maybe. Eduardo is already ruled out.
"Theo Walcott is back and available so Diaby is the only question mark we have. All the others are longer term injuries."
Wenger confirmed that Robin van Persie is not expected to recover from his foot injury until April after a report had stated the Dutchman might be available by mid March.
"For Robin, the rehabilitation is going well but anything before April would be a little bit premature," he said.