I was upset at the nullified punt TD on Sunday, wondering what the refs were seeing, and thinking, perhaps, that Drake blocked his own player and did not do a penalty. But, after looking at the play on all-22, it looks like it was a good call. You can see the illegal block in the circle. In real time you can see he pushes him. The umpire reaches for his flag immediately afterwards, and, since he is behind the play, has a clear view of what's going on the fact that he is far away is not a problem. I am not an expert in officiating, but, I assume the job of the referee and the umpire on a punt, once the ball is in the air, is to move down the field and use their vantage point to seek out blocks in the back that the field judge on the side doesn't necessarily see.