This week in By the Numbers we will look at the newest O’s starting pitcher, Mitch Atkins. Drafted out of high school in the 7th round of the 2004 amateur draft, Atkins moved up through the Chicago Cubs organization quickly. Early in his minor league career Atkins put up good win-loss numbers going 39-19 from 2006 to 2008. However, he reached AAA despite never showcasing underlying skills, such as high strikeouts or low walks, that would support his impressive record. Atkins languished in Chicago never reaching seeing an inning at the major league level and moved to Baltimore this offseason. The table below shows Atkins pitching repertoire from his 2010 AAA season with Chicago and from his start Tuesday night.

2010 Data Fastball Slider Curveball Change-up
Avg. Velocity 88.9 83.4 75.4 82.5
Use Rate 51.2% 36.3% 8.0% 4.5%


07/05 Data Fastball Slider Curveball Change-up
Avg. Velocity 90.6 84.92 78.23 82.6
Max Velocity 92 89.1 79.1 83.4
Use Rate 60.0% 27.7% 8.9% 3.3%

Compared to his most recent full season in AAA Atkins’ fastball usage was slightly elevated Tuesday night, perhaps due to the Rick Adair Effect, and his velocity was up across the board. Atkins’s slider was particularly effective, garnering strikes 64% of time and swings and misses 8% of the time. However, I would be cautious about my optimism when it comes to Atkins’ skill set. Despite not walking a single batter last night Atkins only threw 63% of his pitches for strikes. Usually pitchers with elite control throw a higher percentage of their pitches for strikes. Furthermore, Atkins only coaxed 6 swing and misses during his 90 pitches, yielding a swinging strike rate of 6.7%. Swinging strike rate is the best predictor of future strikeouts. The usual rule of thumb is to subtract 1.5% from swinging strike rate to predict future strikeouts per nine innings. The result is that instead of viewing Atkins as a 7 strikeout per nine innings type of pitcher (2011 Trevor Cahill) as he was Tuesday night, we should view him as 4 strikeout per nine innings pitcher (2011 Mark Buehrle). On the plus side Atkins’ location, especially to left-handed hitters, was excellent. Below is a graph of the the location of each pitch he threw to left handed hitters in Tuesday night’s game.

The graph shows that for the vast majority of the night Atkins stayed away from left handers (inside/outside is the opposite of your expectation on these plots). Of the three pitches that Atkins left over the middle of the plate to lefties, two ended up as hits. Ultimately for a pitcher without swing and miss stuff, like Atkins, to succeed the location needs to be elite. Last night, especially to lefties, his control and location was good enough to produce an effective result. However, be warned that when Atkins misses, as it appears he did on the three pitches to the right side of the plate, he will get pretty hard – like Chris Jakubauskas on Monday night hard.

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