Arsenal manager Arsene Wenger has revealed that he knew about Kim Kallstrom's back injury before officially sanctioning the season-long loan switch late on Friday night, putting a best case scenario for his inclusion in first-team action at the end of February if his recovery goes without a hitch.
Kallstrom is out with a micro fracture in his lower back suffered while in winter training with previous club Spartak Moscow in Abu Dhabi earlier this week, with initial scans not showing up the problem during his Arsenal medical.
A later, more thorough scan later confirmed that the Swedish midfield veteran will not be available for selection until March in all likelihood, with Wenger confirming that he thought about cancelling the loan move before agreeing with Spartak that the Russian giants will pay his wages for the length of his initial absence.
Wenger told reporters in his post-match press conference for the 2-0 win over Crystal Palace: "End of Feburary he will be back as a best-case scenario. With a normal scan you don't find out [about a mirco fracture]. He might play before but Spartak are paying his wages for the first six weeks.
"I would not have signed him as we had two or three more days, but it was Friday night at 5pm and because we might because of the number of games need the players in March and April I thought we'll do it.
"At some stage in our job you have to make a decision. I make this decision because all our central midfielder that have missed part of the season through injury.
"All of our players could miss the next part and I know the player [Kallstrom] very well personally, he has played for seven or eight years in France. He might never play for us or he might score a winning goal in March or April, you don't know."
The 31-year-old will definitely be unavailable for a crucial run of February fixtures that Arsenal also face without Aaron Ramsey and Theo Walcott, with two games against Liverpool plus home clashes with Manchester United and Bayern Munich lying in wait for Wenger's title challengers.