MESA, Ariz. — Sean Doolittle, the ace reliever for the Oakland Athletics, would rather not be known that way. He has a charming impulse to ridicule anything that sounds absurd and self-righteous, even if it is accurate. His Twitter handle — @whatwouldDOOdo — is a pun and a question, a vessel for jokes, but also for good will.

“I just like showing people — and this might be at the root of everything that I’ve done — that I don’t want to be looked at as a baseball robot,” he said the other morning, before an A’s practice. “It feels weird to say there’s more to me than that, like I’m being overdramatic, and a tear rolls down my cheek. But, no — I do like I feel like there’s more to me than just baseball.

“When I was a kid, I remember my parents would say, ‘Baseball is what you do, but that’s not who you are’ — like that might be my job, but that’s not the end-all, be-all. I feel like I might even be able to use it to help other people or open some doors or explore more opportunities.”

Many athletes donate time and money to charities. Doolittle is a strong supporter of Operation Finally Home, which builds houses for wounded veterans and their families. The difference with Doolittle and his girlfriend, Eireann Dolan, a writer and a host on Comcast SportsNet Bay Area, is their willingness to embrace publicly the kinds of causes rarely discussed, let alone endorsed, in the strongly right-leaning culture of the baseball clubhouse.