I think with JSaf likely out, it's time to move Friz to the middle. Lucas doesn't have the lateral movement in defence to play out in the centres. And he clearly proved that he can be a great back rower, arguably our best and most consistent player this season when playing 2nd row.
If i'm being totally honest, i don't think KPP has been playing great. I understand he isn't used great, but he is consistently missing some crucial tackles leading to breaks, and some errors creeping into his game. I'd argue Lucas should be starting on either 2nd row spot.