http://www.twincities.com/sports/ci_...perk-goes-work

Berardino's Sunday feature is on Glen Perkins taking over the role of closer. It's interesting reading the similarities between him and Eddie Guardado.

Both are late-blooming left-handers.Both failed as starting pitchers.
Both got a second chance in middle relief and gradually grew into unlikely closers for the Twins.
Guardado was 31 when he finally opened a season as the Twins' unquestioned closer. Perkins, who turns 30 on March 2, is about to experience the same career milestone.
There is also a lot of talk about the personality needed to be a closer:

"I do spend a lot of time goofing around," Perkins says. "I'm always playing jokes on people. It's a game, and I like to have fun. When it's time to get ready, I get ready, especially when I go out on that field. Once I get the ball in my hand on the mound, I'm a different person."