Better now than later? That's my first reaction to this predicament. Cushing's numerous injuries throughout college are well documented and that was certainly a major concern attributed to him heading into the draft. His senior year of high school, Cushing missed three games due to a similar ankle sprain. In both his freshman and junior campaigns in college, he managed to miss five games due to injury. It's been a recurring theme throughout his career and part of the reason why Tim hates him so dearly (though, that's only a minor factor).
So what exactly does this mean? In the immediate, obvious sense of things, Cushing will miss the first pre-season game and some valuable practice time. Kubiak's exact words on the subject were that he "will be out awhile". Kubes probably isn't up to date on the extent of the injury, as Cushing just recently took the MRI.
Long term, if this is the same type of injury that forced Cushing to miss three games in highschool, things could turn out a little more troublesome than expected. As much as Cushing has been praised throughout camp, he won't get much better by watching Zac Diles from the sidelines. It's essential that he's out there exercising the playbook and refining his technique. That being said, I have no doubt in my mind that he will do all in his power to get better even without playing... whatever that means.
We'll probably know more about the length of his abscense as the day progresses, so stay tuned. More likely than not given Cushing's injury riddled past, this could linger on into much of training camp.