Div I game crew question

[SC Ump]

Being the off season for us baseball/softball umps, I had time to accept an invite to the UGA/UAB game yesterday.

I noticed yesterday, and think I have noticed in the past, what appears to be an extra official standing behind the head linesman. He was on the visitor's side of the field and at the start of the play, he would stand about 5 feet behind the head linesman, well off the side line. I never saw him involved elsewhere, though I didn't watch closely throughout the game. (Did I mentioned the good looking alum that invited me to attend this home coming game with her?)

I believe he had an "S" on his uniform, though there was another side judge actively involved on the field.

Any idea what his duties were? He didn't seem involved with the chains crew.