The prevailing thought is that Olsen doesn't deserve the last spot on the Nationals roster. I really can't say I care, it's the 5th starter for a team with at the very least 3 pitchers it is dying to get into the rotation sometime this year, but it's important enough to merit ESPN mention I can't rightfully ignore it can I? (Ok sure I can - but what else is there to write about?)
JD Martin got sent down so now it's Mock v Olsen. I've said a couple times in the comments that this isn't clear cut because Mock, for all the talent supposedly busting from that arm, has only been good as an older starter in AAA. Yes he's given the Nats organization 150 IP of 2.90 ERA ball with around 8.5 K/9. 2.2 BB/9 and little more than 0.5 HR/9 in AAA over the past 2 years. Those are good numbers, but they almost would have to be for a 25/26 year old in AAA. That's the age where you should be putting it together in the majors, not the minors. Mock has yet to show anything in the majors. Fifteen starts last year of pretty bad pitching, a 5.40 ERA as a starter, who's last 5 starts (5.59 ERA) were no better than his first 5 (5.70 ERA)
Olsen, came into the majors ahead of time. At the age Mock was scuffling through A+ ball (22 if you must know), Olsen had already impressed in AA (over 10 K/9 and the around the same HR rate as Mock, but a few more walks) and was starting for the Marlins. He turned those impressive outings in the minors into a pretty good year in the majors. However, he's has also clearly shown that something went wrong in the past few years and he's probably not going to be able to replicate that early success. His ERA was over 6 last year, in the NL, in not a particularly bad park for pitchers. Still, Olsen is around 9 months younger than Mock (a year younger than Martin) which in theory gives him a little edge and he was injured so you could hope that the injury was the issue all along.
There's your choice.
The 27 year old never was, or the 26 year old has-been.
Or to be less mean-spirited:
The guy who has pitched well recently, but in the minors only and at an age that is getting to be advanced for the league he was in; or the slightly younger guy who has more potential in theory, but hasn't shown it for years and is coming back from injury.
I'm not saying Olsen should get the nod over Mock. I'm saying it doesn't matter. Neither of these guys are "prospects" anymore. Neither of these guys are likely to be in the rotation come July, let alone come 2011. Roll the dice with whoever - it doesn't matter. I would probably go with Mock, just because I want to see if Olsen's arm can hold up before he gets judged in the majors for what is likely the last time. But don't confuse Mock with Desmond. This isn't a guy who deserves 3 months of the Nats time to show his stuff. If he's pitching poor come May 1 and Olsen looks decent in AAA you flip them and you don't look back.