Krenzel played in college for The Ohio State Buckeyes. After quarterback Steve Bellisari was suspended from play due to an alcohol-related police charge late in the 2001 season, Krenzel earned the starting position against Michigan and led the Buckeyes to their first win in Ann Arbor since 1987. His most successful year was 2002, when he led Ohio State to the national championship. Krenzel was 24-2 as a starter (while appearing in 27 games, appearing in relief of Scott McMullen in a loss to Illinois in 2001).