My son, a freshman, thought he would be sharing time between starting and relieving. He was "converted" to a closer early in the season and is still in that role. As others have pointed out, the mental and physical preparation is new and takes time. The ups and downs are tough. So far he has been doing well and likes the fact that he doesn't have to hold anything back when he comes in to pitch. He's happy he's playing and so am I.
As a closer, scheduling trips to see him is more of a challenge but we do what we can.