Arsenal boss Arsene Wenger has confirmed that new signing Kim Kallstrom faces at least four weeks out with a back injury.
The Sweden international made a loan switch to the Emirates Stadium from Russian outfit Spartak Moscow on transfer deadline day, moving to London until the end of the season.
Rumours surfaced that the 31-year-old had injured himself in his first training session with Arsenal.
Yet Wenger confirmed Kallstrom sustained a "micro fracture" in his back shortly before making the move, which Arsenal discovered in the player's medical.
A decision was made to complete the deal anyway.
Speaking to Sky Sports, Wenger said: "It's quite simple; we have to establish the real truth.
"He arrived here and landed on his back two days before.
"It's difficult to get a player of that stature. We did a scan of his back and found he had a micro fracture. Spartak agreed to share the medical costs and I had a decision to make, take nobody or Kallstrom."
Asked when Kallstrom would be ready to feature for the first-team, Wenger replied: "I think the earliest is the end of February, latest mid-March."
Wenger witnessed his side move back to the top of the Premier League on Sunday, as Alex Oxlade-Chamberlain's double secured a 2-0 victory over Crystal Palace at the Emirates Stadium.
And the Frenchman was thrilled to prevail against a stubborn Palace side.
"It was a difficult game," he continued. "We played a well-organised team who are physically very strong.
"We needed to be intelligent and take our chances."
|15||A. Oxlade-Chamberlain||47' 73'|
|Coach: A. Wenger|
for L. Podolski 72'
for O. Giroud 84'
for M. Özil 84'
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