This, the number of weeks he is out at this point is far less important that the long term impact of the injury. The team isn't going anywhere this year anyways so the experience would have been good but his future is much more important.
If it is something like what you mentioned as a strain or a minor tear, etc. then the expectation can be that he comes back eventually fully recovered and 100% capable.
The problem comes in when the injury is the kind of thing that requires a significant surgery, extended rehab, and leaves the player with either limited ability (a step slower) or with an increased chance of re-injury or other injury due to compensation.
Hard for teams to do this but if I'm the Jags I hold him out longer than he or the doctors might say just to make sure that he is 100% coming back.
