Good question (though maybe add Ojeleye, Tatum and Kanter as options?).
This position is really tough to fill. We don't have anyone who's a good option there.
The starting PF should bring something that the other (presumable) starters Walker, Brown, Tatum and center lack.
So it's really dependent on the combination with the center. Maybe a better poll could be what our starting frontcourt should be?
I advocated for G.Williams/Poirier, but Grant Williams looked even smaller in Summer League than I thought he was. Defense is a big issue, so even Ojeleye might be an option for me.