Arsenal striker Eduardo has been ruled out for two weeks with a hamstring injury just days after returning from a broken leg.
The Croatia international only made his comeback after a year out of the first team in Monday's FA Cup fourth-round 4-0 victory against Cardiff.
Manager Arsene Wenger told Arsenal TV Online: "Eduardo is out for two weeks. He picked up a hamstring injury two minutes before I took him off. What a nightmare."
He added: "Nobody knows how it happened but I knew straight away after the game it would be a two-week job.
"It is nothing like he had before but I do know that little setbacks like this are part of being nine months out.
"After that long out nobody plays six months on the trot. It is impossible.
"But at the same time it is a blow because, of course, he can score goals. He had shown that on Monday night."
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