Bartolo has been about as good as could be expected and he looks like a capable back-end starter. He's thrown almost entirely fastballs so far, registering a heater in 98% of pitches thrown according to fangraphs, well above his normal 80% mark. That's going to come down as he settles in, but he's still going to throw his fastball more than any starter I'm aware of. He can do it because he throws a variety of them and his command is excellent. It's a formula that's worked for him for a long time. And he'll probably be well prepared to face Oriole righties with his stuff.
The problem is that the O's are only going to send 2 righties to the plate worth talking about. Whoever catches for them until Wieters gets here can't hit, so it's Adam Jones and Ty Wiggington that will likely be tied up for much of the day. Against RHB in '08, Colon allowed a.253/.266/.293 line with a .302 BABIP against. No pop, no walks. Jones and Wiggington have power enough to make Colon regret a mistake, but that's about it.
Unfortunately, Roberts, Markakis, Huff and Scott will all bat lefthanded against The Rotund One. Bartolo has walked 3 lefties in 27 PA this year and walked 9 in 92 PA last year. That's bad and probably indicates Bartolo is pitching around hitters he doesn't think he can get out. With so many lefties in the lineup, Colon is going to have to pick someone to throw to. The results so far this year have been seriously aided by BABIP and if '08 is any indicator, it's not going to be pretty: .309/.385/.556 with a .317 BABIP. While Colon won't be as handicapped as Conteras was by his inability to throw anything offspeed for a strike to a LHB thanks to superior fastball command/variety, he's yet to demonstrate aptitude with his change-up necessary to allay worry. In any case, it looks like it'll be a slugfest today.