Won't matter. By the end of the season everyone will know who he is if they didn't find out last year, especially if the A's make the playoffs.
And speaking of underrated, you also gotta take a look at Barry Zito. I'm especially pleased about his performance this year, mainly because I was one of the few who stuck with him and didn't give up on him when people were saying he was done earlier this year. He has too good of stuff, and his mental approach to the game is too good for him to stay down for long. So for him to bounce back had been a pleasure to watch. Him and Harden make up a terrific 1-2 combo, and now with the emergence of Haren and the continued development of Joe Blanton, the A's are going to be fine. I'll bet Billy Beane is glad he didn't trade Zito when people were telling him to, saying he needs to get rid of him while he's still worth something. So in that sense, Zito has also been underrated.