The Boston Red Sox had an event at Fenway a couple weeks ago, allowing their Triple-A team to have their game there. The opposing team turned out to be the Norfolk Tides, and Brooks Baseball has the pitch/fx up for it. The Tides starter in the game was the final member of the Big Three, Jake Arrieta. I haven't seen Arrieta pitch before, so this will be my first look at his stuff. His line for the game was 6 IP, 6 H, 2 R, 0 BB, 4 K by the way, plus the win.
The fastball was quite good - as it should be based on the scouting reports. It touched 97 and average 94 mph, and had a little above average movement. The change-up was very hard, averaging 86 mph, and while it doesn't sink too much it does have a good amount of tail in on right-handers. Like David Hernandez, Arrieta's breaking-ball is categorized as sometimes a slider and sometimes a curveball. Given the velocity (84 mph), I'd lean towards the former, but a couple of the pitches did have some big break to them. I don't know if this could potentially be a problem down the line, but everything Arrieta throws is quite hard. There is a pretty good gap in velocity between the fastball and the change-up though.
Like Hernandez and Tillman, Arrieta threw a lot of pitches up in the zone. That partly allowed him to get a lot of called strikes with his breaking pitches, but it didn't result in any swings and misses (same issue Hernandez had). I understand throwing the occasional high fastball when you can zip it in there at 96, but if you live up there things are generally not going to end too well.
I think it shows that at this point what the O's young starters need to do is really work on locating their pitches, especially down in the zone. If they can do that, I see no reason why the Orioles can't have an above average rotation in the very near future.