For whatever reason, I’ve been a big fan of David Robertson since he came up to the Majors in 2008. If I had to nail it down, it’s probably the strikeouts that have drawn me to Robertson. There’s nothing I like more than to see a Yankee pitcher rack up the whiffs, and that’s what he does (oh who am I kidding; I just love the high socks like the rest of you). I’m also higher on D-Rob than many are; I think he’s got the right two pitch combo to be a closer when the time comes. His relative lack of control may hurt those chances, but he does back up the walk numbers with wonderfully strong strikeout numbers; his lowest K/9 was last year’s 10.42 mark. As for the walks, they’re trending downwards this year.
After slight increases in BB/9 over his first few years, Robertson is bringing the walks down this year. I don’t think he’ll ever have Mariano-like control, but I do think he can continue this trend. In fact, so far this year, Robertson has thrown a career high 55.8% of his first pitches for a strike. This tells us that Robertson’s been a bit more aggressive on the first pitch and that could be helping fuel his hot start.
Along with the increased first strikes have come increased swing and contact rates. Batters are offering at more pitches from Robertson, 47.6% to be exact (compared to 39.6% for his career). They’re swinging at more out of the zone, too (31.3% 2011; 21.3% career) so Robertson is getting potential hitters to chase a lot more which is a good sign.
Despite that chasing, though, batters are making more contact, 82.4% 2011, 77.3% career. But once they make contact, things aren’t going so well. His BABIP against is .360, but his tRA is super low at 2.12, good for a tRA+ of 152. This graph also shows us something nice about Robertson’s development:
Robertson’s groundball rate is trending upwards while his fly ball rate (and HR/9 rate) is trending downwards. If Robertson is able to keep that trend up, he will ascend to elite reliever status. We always want pitchers to get groundballs and strike batters out. Robertson already had the latter nailed down, and it looks like he’s getting the hang of the former.