Sources tell me meniscal tear, which usually makes up part of what is called the evil triad, as it typically accompanies ACL and MCL tears. Could be speculation and rumor, though, as you say. If it is meniscal only, they are notoriously slow to heal, and still would likely take longer than 4 weeks.
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The other option if he is healed up, McCray can play the linebacker spot. He has always been a tweener LB/S anyway.
