I actually think he's worked it out, but it's not been available just recently.
Ryan, Lamptey, White, Dunk, Webster, March, Alzate, Bissouma, Lallana, Trossard, Maupay.
That line up has been available for just about every match this season, apart from Dunk, for whom we have excellent cover, and maybe a couple of matches where Alzate might have been a bit jet-lagged. To be fair, Potter has stuck pretty much with that defence, but he's chosen to do a lot of tinkering in front of it!