If service time issues had nothing to do with the decision, I don't think there's any question that Britton would have made the team out of spring training. That's usually the case for impressive top prospects, and many decisions are made because of their future financial impact. Again, for Britton, all of that will depend on several factors: how well he pitches, which other starters get hurt or stay healthy, whether or not the O's are winning games, among others. And there will be plenty of time to worry about the service time/team control issue later in the season if it's still a concern (which will mean that he's still on the roster).
But today Britton, probably the O's top prospect at this very moment ahead of shortstop Manny Machado, will make his first start in an O's uniform. Britton joins a stable of young O's starters: Matusz (24), Jake Arrieta (25), Chris Tillman (almost 23), and Brad Bergesen (25).
Don't know much about Britton? He was selected with the 85th overall pick (third round) in the 2006 MLB Draft. Starting rookie ball that same year, he rapidly ascended through the O's system. In 2010 he started the season at Double-A and impressed quickly: He ended up only making 14 starts there because he dominated the competition (2.48 ERA, 7.03 K/9, 2.90 BB/9, 0.41 HR/9). After those starts, which only amounted to 87 innings pitched, Britton moved to Triple-A, where he was nearly as solid in 12 starts (66.1 innings): 2.98 ERA, 7.60 K/9, 3.12 BB/9, 0.41 HR/9. Some of the concern surrounding Britton has to do with how little he's pitched above Single-A. However, the O's believe that he deserves an opportunity to pitch in the majors right now, and he could always return to Triple-A at some point during the season to get more seasoning at the minor league level.
This Roch Kubatko article for Baseball America (written on March 25) does a good job explaining what makes Britton so effective:
"His fastball's unbelievable," catcher Craig Tatum said. "He throws hard and the ball moves. He's got really good sink on the ball, keeps the ball down, goes right after hitters. He says his changeup's his third-best pitch, but with his fastball, he doesn't really need to throw too many off-speed pitches because his ball moves so much. When he figures it out with the slider, he's going to be good."A young lefty who throws a ton of two-seamers with great movement that induce ground ball after ground ball? No wonder there's so much excitement surrounding his promotion.
"The ceiling is sky high," Norfolk pitching coach Mike Griffin said. "I still think there's more in there from him that we can still see from Zach. I don't think he's reached his ability yet. He's still got a ways to go to improve and get better and be even better than he was when he was with me last year. The fastball has great life. Not good life, great life. And it's late and it's hard. He's learned to spot it up, have better command of it. The slider has come a long way from when I first saw it. It's a little bit quicker now, little bit sharper, little bit more depth to it. We've made a lot of progress trying to get him to backleg it to righthanded hitters.
"The changeup, he's still working on it. He's still trying to get consistent command on it. But what impressed me last year was, he was still working on it, but in his last two starts he threw changeups on 3-2 counts and got hitters to swing and miss at it. That tells me the kid has gained a lot of confidence in that pitch."
Britton induced lot of ground balls last summer while going a combined 10-7, 2.70, with 51 walks and 124 strikeouts in 153 innings at Norfolk and Double-A Bowie. The pattern has continued this spring. Only one out against the Astros came on a fly ball, to the last batter he faced in the fourth inning.
"He keeps the ball down," Tatum said. "He'll be like, 'I didn't hit my location that time,' and I'm like, 'I don't care where the ball is if they keep beating it into the ground.' I just like the way he attacks hitters. And once he gets the feel of his slider better, he's going to be good. I'm glad we have him in our organization, because I don't want to face him."