It was the kick catch interference. One score game and Houston would have the ball with a short field and not much time on the clock.

By the way here is the rule...

ARTICLE 1. a. If an inbounds player of the receiving team is located where he could catch a free kick or a scrimmage kick that has crossed the neutral zone, and if he is attempting to do so, he must be given an unimpeded opportunity to catch the kick.
b. It is an interference foul if, before the receiver touches the ball, a Team A player enters the area defined by the width of the receiver’s shoulders and extending one yard in front of him. When in question it is a foul.