It's hard to handicap precisely how long Devin McCourty's high ankle sprain will keep him on the shelf.

If it's a Grade 1 sprain, he could be back in a couple of weeks. A Grade 2 or 3 sprain could keep him out for the rest of the regular season. So what does this mean for the Patriots safety rotation?

The Patriots could put Duron Harmon in the McCourty role where Harmon would be asked to be a sideline-to-sideline rover, giving help over the top and communicating the coverages. It's debatable as to whether or not Harmon has the speed and closing ability to do the job as well as McCourty, one of the fastest safeties in the league.

If the Patriots don't feel comfortable with that, you can expect more two-deep safety formations with both Patrick Chung and Harmon splitting the field. The Patriots would then deploy either Nate Ebner or Tavon Wilson in the Chung role.

One good thing for the Patriots is the experienced depth they have at the position. McCourty's a Pro Bowl level player but the experience and intelligence of the other safeties on the roster should help mitigate the loss.