We're not two days into San Francisco 49ers training camp, and the injury bug is biting already. That of wide receiver Christian Kirk. That seems a safe bet as we sit here today, but as Kirk misses more time, that becomes less likely. So, if I was the two young players closest to the Niners' wide receiver bubble, I'd be walking into meeting rooms and demanding (possibly pleading) to learn the slot role. Either way, Kirk's injury has thrown an interesting wrinkle into one of the most fascinating camp battles on the roster.