Can you name the Braves' rookie with the highest strikeout rate in 2009? The title of the post probably gives away the answer, but be honest: you were thinking Tommy Hanson. Hanson has stolen the spotlight for the Braves this season, but it's difficult to overstate the contributions and progress made by Hanson's close friend and longtime roommate Kris Medlen. Medlen may not look like much at 5'10" and 190 pounds, but he's got it where it counts with three major-league caliber pitches that he mixes well. Since he lacks any one blowaway pitch, he's often been characterized as a control-reliant pitcher, but interestingly he's actually looked more a dominating if somewhat wild at the major-league level (3.99 BB/9 is fairly high, but he's also kept his K rate up over 9.5).
I remain incredibly intrigued at Medlen's potential as a starter; some scouts cite his small frame as a reason to be concerned about his durability over the course of a 200-inning workload. However, he's got a stress-free delivery, and his broad arsenal seems like it could pass muster in a major-league rotation. I've mentioned this in comments before, but prior to the season, Medlen's #2 PECOTA comparable was another smallish, converted position player: Roy Oswalt. Of course expecting Medlen to become the next Oswalt would be unrealistic, but I think the point is that there's plenty of reason to be optimistic about Medlen's chances to be a useful mid-rotation arm. Sure, it's lovely to have reliable relievers, but when you could have a reliable starter instead, you take the starter any day.
As crowded as the Braves' rotation might look these days, I worry that if Medlen gets too accustomed to relieving, it'll be that much more work to have him join the rotation someday. Still, it seems obvious that his near-term role will be at the back end of the bullpen, and there's little reason not to expect him to have plenty of value in that capacity. Still, he's the reason why I wouldn't hesitate to trade a starting pitcher this winter; while some want to keep all six to maintain depth, I'd argue that Medlen steps right in as a new sixth option for the rotation.
The bottom line: He'll likely spend another year as a versatile, high-leverage reliever in 2010, but there's still hope that he could turn into a valuable starter someday; look for him to get an extended shot if trades and/or injuries deplete the rotation at any point next season. Either way, don't let Tommy Hanson's shining star blind you to Medlen's considerable potential.