Breaking Down Brian Matusz

A four-pitch lefty taken fourth overall in the 2008 draft, Brian Matusz shredded minor league bats during his pro debut — in 113 innings split between the High-A Carolina League and the Double-A Eastern League, the San Diego star whiffed 9.5 batters per nine frames, walked 2.5 per nine and compiled a 3.02 FIP. Matusz reached the Charm City less than a year after he and the Orioles agreed on a major league contract worth a little more than $3.4 million. He placed fifth on Baseball America’s list of the best farm talents in the game prior to 2010, and Matusz recently ranked #44 in Dave Cameron’s Trade Value series. Suffice it to say, Matusz comes with quite the prospect pedigree.

While there’s plenty of reason to believe he’ll emerge as a valuable commodity to the O’s and fantasy owners alike, Matusz holds a 5.11 ERA through his first 32 starts at the big league level. Now that the 23-year-old has pitched at the highest level for a little more than a year, this seems like a good time to examine what the former Torero needs to do to avoid getting gored by hitters.

Matusz has 7.12 K/9 and 3.36 BB/9 in 174.1 innings pitched. While he showed slight ground ball tendencies during his short stay in the minors (48.1 GB%), the 6-5 southpaw has gotten grounders just 35.4% of the time in the majors. That has led to his giving up 1.08 homers per nine innings, despite a home run per fly ball rate (8.5%) that’s below the 10-11% MLB average. All of those fly balls are concerning, given that Camden Yards increased the rate at which flies turn into souvenirs by 15 percent over the 2006-2009 seasons. If Matusz had given up home runs on fly balls at an average rate (11%) on the road and 13% at home, he would have served up over a homer and a half per nine innings instead.

In a couple of other respects, however, Matusz has been unlucky. He’s got a .331 BABIP, which is very high for any starter, much less an extreme fly ball pitcher. While the flies that aren’t caught are generally quite harmful, fly balls do have a lower BABIP than ground balls. Matusz’s BABIP on flies is .165, while the AL average is closer to .140. He also has a .781 BABIP on line drives, compared to the .720-.730 AL average. We don’t yet have enough information to say whether that’s noise or something more significant, but odds are his BABIP falls.

His rate of stranding runners on base (68.6%) my creep into the low-70’s, too — based on this formula developed by Dave Studeman, Matusz’s LOB rate should be closer to 71%. Overall, Matusz’s expected 4.65 FIP (xFIP), based on his rate of K’s, walks and a normalized HR/FB rate, is nearly a half-run lower than his actual ERA.

Matusz has gone to his 90-91 MPH fastball about 63% of the time, adding in a low-80’s changeup (19%), a mid-70’s curveball (10%) and a low-80’s slider (8%). That expansive repertoire has garnered swinging strikes at a near-average clip (8.3%). He’s putting plenty of pitches within the strike zone — 54.3% last year (49.3% MLB average in ’09) and 49.2% this season (46.8% MLB average). Opponents are making contact with those in-zone offerings just 85.5% (87-88% MLB average). However, they’re getting the bat on the ball often when swinging at pitches thrown off the plate. Matusz’s O-Contact rate was 65.7% last season (61.7% MLB average in ’09) and it’s 73.9% in 2010 (66.6% MLB average).

Against fellow lefties, Matusz is a monster (11.47 K/9, 2.39 BB/9, 3.18 xFIP). Right-handers, by contrast, aren’t trembling at the prospect of facing him (5.93 K/9, 3.62 BB/9, 5.06 xFIP). Check out his whiff rates by pitch type versus lefties and righties, from

Keep in mind that the sample sizes aren’t massive here. That being said, opposite-handed hitters haven’t been fooled near as much, especially against Matusz’s fastball.

Brian Matusz remains a keeper-league favorite, but he’ll have to overcome his fly ball proclivities and find a way to make righties come up empty more often to take the next step in his career.

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A recent graduate of Duquesne University, David Golebiewski is a contributing writer for Fangraphs, The Pittsburgh Sports Report and Baseball Analytics. His work for Inside Edge Scouting Services has appeared on and, and he was a fantasy baseball columnist for Rotoworld from 2009-2010. He recently contributed an article on Mike Stanton's slugging to The Hardball Times Annual 2012. Contact David at and check out his work at Journalist For Hire.

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The MLB Average home run per fly ball rate (7.2%) is below the 10-11% MLB average. And it’s really showing up in inflating the xFIP numbers this year.


Sorry for any confusion, but I’m confused. I was using bbref numbers for HR/FB, which is the 7.2% number. I see the number here is higher (but still not averaging the 10.5% used for xFIP), but I have no idea how such an objective number can be so different.

Lucas Apostoleris

I don’t know for sure, but maybe B-Ref is using home runs per ball in air (which would include line drives and possibly pop ups) as opposed to outfield fly balls.