I'm pretty convinced at this point that Penny is going to be the odd man out. One start doesn't mean everything but it isn't as if this is his only sub-par start. I think Buchholz deserves a chance to provide a spark to the team and be the full-time starter. What more could he have done? Dominate the minor leagues, then give us a good start where he only allows 1 ER in 5.2 innings. What do you want, a no hitter? He's better than Brad Penny and all you have to do is watch them to know that.
On another more positive note, aside from Penny's struggles..isn't it really amazing how every year Pedroia finds a way to improve? Look at his on base percentage, it's actually higher this year despite a batting average 21 points lower.
His OBP this year is .380 as of this moment after his last walk, compared to .376 last year. I know it's minimal but his walks total is more impressive to me. He had 50 walks all of last season and he already has 42 this season in 72 less games played.