Yes, free safety. If Jones moved, he would essentially become a backup, playing fewer than 50% of the defensive reps.
Devin McCourty led the Patriots in defensive snaps for a decade, or was close to it. You put your best players on the field.
I think that the reality is the secondary coaches are fine with having Dugger and Peppers play over 90+% of the reps every game that they are available. I suspect think that the secondary will be effective as long as they get good play from beyond the top four starters.
Mapu may be a weak side linebacker now, but he still factors into snap's played if he makes the second year leap rookies have to make to be good/great. if he becomes a starter or max snap guy, they play Duggar Peppers and Mapu as a LB, but titles be damned... they don't want other teams deciphering who the SS, LB or even FS is on a given play. The Pat's D have disguised that better than anyone over the last two decades.
I think that the staff is fine with Jon Jones playing 90+% of the reps, starting at corner, as well as Gonzo playing 90+% of defensive reps.
Somebody will have to play free safety, I didn't give him the job; Jon Jones, Shaun Wade, Marcellas Dial, Isaiah Bolden, Azizi Hearn... any of these guys potentially has the athleticism to do it.
Jon Jones is faster than any of them and you want speed at the position. He's more experienced, can play facing the offense and cover. I don't know what his thoughts on the idea are, but they might also have somebody slotted there in their minds. Either way, camp competition will sort it out.
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SO, TO START
We have Jon Jones, Gonzo, Peppers and Dugger all expected to play all the reps for which they are available.
As is, someone (or two) will be the 5th starter (nickel, 2 outside CB's, and 2 S). IMO, we should have a decision for only one starting roster spot. If you move Jon Jones, he is no longer a starter, and we now need two starting CB's.
DEPENDING ON WHERE JON JONES STARTS THE FIFTH STARTER COULD BEs
slot CB Marcus Jones
slot CB Wade
outside CB Wilson
Outside CB Austin
Outside CB Bolden
free agent CB Gilmore
BACKUPS
We have lots of possible backups at CB.
My issue is that I would like to have another backup S (preferably a free safety)
This is my projected depth chart with Jon at FS for kicks, I added weak side linebacker to the group since we're talking about coverage mainly and Mapu is a hybrid.
WLB – Marte Mapu, Sione Takitaki, Christian Elliss,
Joe Giles-Harris (PS),
SS – Kyle Dugger, Jabrill Peppers, Brenden Schooler, Jaylinn Hawkins,
Josh Bledsoe, Dell Pettus (PS),
FS – Jonathan Jones/Shaun Wade,
BIG CB – Christian Gonzalez, Marco Wilson, Marcellas Dial, Isaiah Bolden, Azizi Hearn,
Alex Austin (PS),
SLOT CB – Marcus Jones,
Kaleb Ford-Dement (PS),
Brenden Schooler and Jaylinn Hawkins mostly play special teams, but one or the other could be a break glass in case of emergency replacement.