If the team starts 2 bigs and isn't Griffin, then something has gone horribly wrong.
If Vonleh plays similar to how he did last game, I wouldn’t be surprised if he makes the team and starts over Griffin.
Griffin may be better than Kornet or Vonleh once fully integrated with the team but the problem is that he hasn't been with the team enough yet to be fully integrated. That is the advantage that Kornet has over Vonleh and Griffin. Missing these 2 weeks has not been helpful for Kornet though. I don't think Vohleh should start. Let him come off the bench. Not a lot of good options for Celtics.
To me, it is not about who the better player is, it is more about which player allows the other 4 starters to play the best. I think the initial thought was that Kornet could be the one to just fill the role and let the other starters do their thing. Maybe Griffin can get there, he is a vet, should be able to pick things up quickly, but he has never played with the other starters before. We will probably see some of Griffin with the starters on Friday.
The other option is to go small. I don't like that. It does allow for more talent on the court (say Brogdon over Griffin/Vonleh/Kornet). But then Brown and Tatum are both out of their natural position or the position that they would play in a 2-big line up (and was the core line up last season). I know it is not the end of the world if Brown is at SF instead of SG, but it is something to make the unit that much different. You don't want the other 4 starters to have to adjust to the 5th starter. You want the 5th starter to make is so the other 4 starters don't have to adjust. It may end up the lesser of several options. Maybe Griffin plays with the starters on Friday and looks great. That would make the decision easier.