Since 2000 Utah and Utah State have played 13 times, overall they have meet 112, and it's the 14th oldest rivalry in college football. That is if you consider it a rivalry, the series has been mostly dominated by the Utes, they have won 72% of the games played between the two schools, and over the last 15 meetings they have won 14 times.
The one-sided domination of this series obviously raises the question "Is this series even a rivalry?". While the question is simple, the answer is not.
In the NCAA's eyes, this series is a rivalry, called the "Battle of Brothers".