was standing there unmarked prior to the snap on 3rd and goal at the 1?
Instant replay from field level showed Stroman appearing to be setting up off the right side of the Pitt line when he glances over his left shoulder to see the receiver all alone. So he runs over to cover, getting there just in time to disrupt the play.

Kentucky (up by 6) lost to Florida earlier in the season on a similar play where the receiver was not marked.