What's Up With Brian Matusz?
For a second start in a row, Brian Matusz wasn't even able to get 10 outs as the Blue Jays knocked him out after 1.2 IP and 6 runs allowed. Matusz was a popular Rookie of the Year pick coming into 2010 - he was my selection as well, and not in a partisan way - but he seems to have really regressed from his solid showing at the end of 2009. His ERA (5.21), FIP^ (4.43), and xFIP^ (4.74) are all up around half a run, and there's some talk of sending him back down to the minors. What's going on with (still) the O's top pitcher?
First of all, he's striking out fewer batters (7.7 K/9 to 7.1) and walking more (2.8 BB/9 to 3.4) than he did last year. Matusz was never supposed to be a power pitcher, and the strike-out rate is still a touch above average - he can live there just fine. The walks are a little surprising though, since Brian was billed as having plus control - and his mark this year is actually worse than average. It's odd, since Matusz throws an above average percent of his pitches in the strike-zone according to FanGraphs (though less so than '09). Anecdotally, it sometimes seems that when he loses control he really loses it - and the number back that up (to a degree), as he's walked 45.5% of batters that have gotten to three ball counts against him compared to 42.5% for the average AL pitcher. Breaking it out by count: after getting to 3-0 he ended up walking the batter (in that plate appearance) almost 73% of the time (64% AL average); after 3-1 it's 50% (43% AL); and after 3-2 it's 35% (31% AL). Maybe that's a sign that Matusz occasionally has his mechanics get out of whack - I don't know. I think it's a good bet that he'll improve in this area, but I'm not sure he'll get it much under 3 free passes per nine for a little while yet. His control has really abandoned him in these last couple shellings, as he's walked 6 batters in 4.2 IP.
Then there are the home runs. Matusz has been an extreme flyball pitcher so far in the majors, even though he got a good number of groundballs in the minors. It's a problem since - as I often say - if you allow batters to put a lot of balls in the air, eventually a bunch of them will find the seats. Despite giving up more home runs than the average pitcher - 1.11 HR/9 (0.95 HR/9 average) - he's actually been a bit fortunate so far to give up as few as he has. Only 8.8% of balls in the air have gone for homers in 2010, and it was 9% last year. Pitching half his games in Camden Yards - and against the slugging AL East so often - you'd expect that to be a little higher. Matusz has been able to induce a fair number of pop-ups - which turn into outs at a high rate - so that helps things. Still, getting the ball down a little more would be nice - especially since he doesn't have the velocity to blow the fastball by hitters up in the zone. Here's a graphic of Matusz's pitch height, along with all left-handed pitchers:



