Honestly at this point I'm among the people that feel sorry for the guy. This is his big break and it could not be any more disastrous. I'm sure he was ecstatic when he got the call, and anytime you get a huge opportunity it sits in the back of your mind "what if?" "What if I come out and my team just can't score?" "What if I lose my first game to a cupcake team?" He's living that reality right now and I doubt he's sleeping well at night. The poor guy looks like a whipped puppy in his interviews and the people interviewing him are just beating him over the head and he obviously doesn't know how to handle it.
Now on the flip side of that, he's also completely screwing over Patton Robinette. PR is clearly, indisputably, undoubtedly the better of the 2 QB's and was even named the starter, only to be pulled after going 4-6 in his first 6 throws. He hasn't seen the field since. Mason obviously just liked Rivers better and was always looking for a reason to put him in, regardless of the fact that Rivers is awful. I mean..... terribly awful.
But yeah to answer the OP in short, they lose to UMass this weekend and he doesn't make it through the season.
Side note: in all this I certainly don't feel sorry for their fans, not in the least bit. Screw their fans. I saw a post the other day after the Ole Miss game that said "UT doesn't look good. They've played a couple of cupcakes and struggled. But with the way we're playing even they could probably beat us."
Unbelievable.