Kris Medlen has certainly turned his season around as of late. After a somewhat rough start to the season where many questioned if he should be sent to the bullpen upon Brandon Beachy's return, he's hit a hot stretch, looking more like
Greg Maddux the 2012 version of himself. He had a spectacular June and is now sitting on a 3.02 ERA to go along with a 3.80 FIP and 3.98 xFIP in 98.1 innings.
If you really strip it down, his success can most easily be seen in two simple stats, strikeouts and walks. Both of these are two basic, but useful indicators of a pitchers success and how sustainable you can expect the success to be going forward. Below is the table of Medlen’s monthly K% and BB%.
As you can see, he has improved as the season has progressed. His BB% was absurd in June, he only issued walks to two batters the entire month. To go along with that, his strikeout rate has also gone up back to his career level. Both are obviously positive signs, even if the walk rate isn't sustainable. So what has caused this change?
If you're looking at the big picture, his command has certainly improved. He has gone back to the pitcher who can throw any pitch in any situation with plus command. One could assume he finally straightened out the mechanical issues he was tweaking earlier in the season with Roger McDowell, thus the drop in walks. Improved command and control will lead to improved results almost every time, especially for a pitcher like Medlen.
Something that stood out to me are his 2013 splits. During his career, Medlen was known to have a marginal reverse platoon split due to his great change-up that held left-handers in check. However this season, it’s been the opposite. If you look at his FIP (2.92 v. RHB, 4.53 v. LHB) and xFIP (3.02 v. RHB, 4.76 v. LHB), you see a much different story from past seasons. Early on in the season, Medlen noticeably went away from the change-up v. LHB, something that seems to have since trended back towards normal usage rates (only a 2% drop off now from 2012). He still hasn’t thrown it as frequently as a put away pitch, that being ahead in the count or with two strikes, but he has appeared to regain the touch and feel for it and it throwing if with greater frequency (since CAC is no longer up and running I can’t pull the raw data from earlier in the year as a comparison point, but the usage has gone up). Remember these splits are a half season worth of performance, so there is still a good amount of randomness going on. We can reasonably expect him to regress back to career levels and fare worse v. RHB, while having more success with the change-up v. LHB as the season continues.
One other interesting note that jumped out was what looks to be the addition of a cutter in June. We must always use a bit of caution with PITCHf/x classifications and pitches being mislabeled, but there definitely looks like he has added a pitch. He has thrown the cutter the majority of the time v. RHB, a possible and partial explanation for why he has had such great success v. RHB. I don't what else to make of it quite yet, but it is something to keep an eye out for to see if it's a pitch he sticks with.
Stepping back and looking the big picture, there are still some of the same unanswered questions with Medlen that were brought up at the beginning of 2013. The most asked question is the increased workload, which I have previously stated that I think he’ll be alright with. Just because he’s never had the opportunity to amass a large amount of innings, doesn’t mean he can’t; he's just never been given the chance being bounced back and forth between starter and reliever. In addition to that, he has a clean easy motion that doesn't raise any immediate red flags for future injury concerns (see: Hanson, Tommy). In all reality, this is an "issue" we won't have an answer to until the end of the season.
Medlen has definitely been intriguing this season; we've seen the good an the bad all within three months. To be honest, I don't exactly know what to expect going forward because of some of the changes he's undergone besides giving the easy answer of "somewhere in the middle". This stretch of success should continue tonight when he takes the hill against the Marlins lineup.
Data courtesy of Brooks Baseball and FanGraphs.