Shearer excelled in both indoor and outdoor track during his career at Harvard. He earned three first team All-Ivy nods in the 1000 meters and All-East honors for the 1000 meters in 1993 and the steeplechase in 1994. According to Coach Frank Haggery '67, "Darin [was] one of the most versatile athletes I've ever coached, and he was willing to run in any event to help the team succeed." Shearer still holds the school record for the steeplechase, turning in a time of 8:45.02 at the Heptagonal Championships in 1996. He also qualified for the Olympic Trials and was named and All-American for steeplechase in 1996.