The Swede could make his debut today against Tottenham.
"He is a fantastic guy. His motivation and attitude has been spot-on," said Wenger. "He can play an important part in the end of our season. We are all delighted to have him.
"It possibly was a cause of embarrassment with his signing and injury. But as I explained, we did not pay. We found a good agreement with Moscow Spartak. At the end of the day it was sign him or nobody.
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