When Jake Arrieta won his Major League debut on June 10 against the Yankees he became the latest pitching prospect to come up to the Orioles from the minors and enjoy instant success. But when he followed it up with a win in San Francisco to improve to (2-0), he broke a trend by winning his first two big league starts. Last season Brad Bergesen, Jason Berken, David Hernandez, Chris Tillman and Brian Matusz all made their major league debuts for the Orioles. Bergesen, Berken, Hernandez and Matusz all were winners in their first starts. Tillman, who pitched to a no-decision on July 29, 2009 versus Kansas City was the lone member of the group who didn't win in his first big league start. Here's how well the five combined to pitch in their first major league starts: (4-0), 2.77 ERA in 26 IP, 10 R, 8 ER, 3 HR Their follow up starts however produced different results. None of the five lost their big league debuts, but none won in their second starts. Berken, Hernandez and Matusz all lost their follow up starts, while Bergesen and Tillman pitched to no-decisions. Here's their combined pitching line in their second starts, which shows a big drop off in effectiveness: (0-3), 7.56-ERA in 25 IP, 21 ER, 8 HR There are a number of reasons for the differences in the first to second major league start, and the most probable is scouting. When a pitcher first comes up from the minor leagues, there is a scouting report on him, but very little video. The hitters are at a disadvantage having never faced a pitcher. But once a pitcher appears in a big league game, there's video available to dissect and a scouting report filed by a major league scout whose job it is to find trends to try to exploit. It's about adjustments. That's what makes Arrieta's (2-0) start so impressive. He beat a potent New York Yankees lineup in his first start with an impressive line: 6 IP, 3 ER, 0 HR. He also got out of a bases loaded jam in his final inning, which put him in a position to win the game. Then in his second start against the NL West contending San Francisco Giants, he was even better. He was dominant. Arrieta pitched one batter into the eighth inning. He allowed 1 run on just 3 hits. He struck out 3 and walked 2. He retired the side in order in four of his seven full innings. His numbers after 2 starts are impressive: (2-0), 2.77-ERA in 13 IP, 4 ER, 1 HR He has shown an ability to pitch to contact and shows a poise beyond his limited professional experience. Jake Arrieta is everything you want to see in a prospect. He earned his way to the big leagues by dominating the International League, and now he is earning rave reviews in the majors. He's giving the Orioles a boost exactly when they need it.