Penn State and Pitt have played only twice since 2000, but they’ve met 98 times with history that pre-dates the forward pass by 13 years. Ohio State and Michigan have met 113 times, forming perhaps the greatest rivalry in college football. Rivalries develop because of the accumulation of history and stories and memorable moments over the course of decades. They need time to grow.
Penn State-Ohio State is a young rivalry that is still, in some ways, a teenager compared to the more established and more historic series. Although the Nittany Lions and Buckeyes have roots dating back to 1912, they have met only 32 times: eight times before Penn State joined the Big Ten and 24 times as conference brethren. Since Penn State began Big Ten football play in 1993, Ohio State is the only team it has played in every season, and that includes today in Columbus:
http://www.sportsonearth.com/article/259674024/penn-state-ohio-state-big-ten-rivalry-growth
