In his first two Minor League seasons in Class A and Double-A, Parker put up back-to-back seasons with an ERA under 4.00. In his first professional season at Class A South Bend, the 19-year-old Parker struck out a batter an inning. In his second, he duplicated that feat while lowering his ERA against tougher competition.
But an October shoulder surgery that year kept him from throwing a competitive pitch for an entire year. And this spring, Parker, now 22-years-old, made his return to the mound for Double-A Mobile, still ranking at the top of the class of D-backs prospects.
In 11 starts at Mobile, the top-of-the-rotation projecting Parker has a 4.75 ERA. He is 5-4, still maintaining his strikeout rate at close to a batter an inning while walking more than he has in the past. Parker has walked 23 in 53 innings.
Wade Miley, the 43rd overall pick in the 2008 draft, was the organization's next-best pitching prospect behind Parker, and the left-hander pitched well at two levels last season.
In his third season of professional ball, Miley bounced from Class A Visalia to Mobile and sported a cumulative 2.65 ERA. He struck out 113 in 153 innings and walked 65.
This season, the 24-year-old is trying to regain his footing, coming out of the gate with a 7.19 ERA in 10 starts.
But with last year's midseason trade of Dan Haren to the Angels came 19-year-old Tyler Skaggs, a left-hander drafted by Los Angeles in the first round of the 2009 Draft.
After the trade, Skaggs made four starts in South Bend and allowed only three runs, while striking out 20 batters in 16 innings. This season, at Visalia, Skaggs has continued his torrid strikeout pace with 90 in 73 innings, recording an ERA of 3.21 in 12 starts.
According to MLB.com's draft and prospect expert, Jonathan Mayo, Skaggs is the No. 2-ranked prospect in the D-backs organization and ranks as the No. 10 left-handed pitching prospect in the game.
Offensively, first baseman Paul Goldschmidt has been tearing the cover off the ball in the Minor Leagues. Last season, Goldschmidt, an eighth-round pick in 2009, earned MVP honors in the California League in Visalia, and was named D-backs Minor League Hitter of the Year.
This season, Goldschmidt has picked up where he left off, smacking 19 home runs in 59 games. The 23-year-old has a .344 batting average at Mobile with 53 RBIs. He has also cut down on his strikeout rate and looks to punch a ticket to Triple-A Reno very soon.
Other players that rank in Mayo's top 10 prospects in the organization include third baseman Bobby Borchering -- the team's 2009 first-round Draft pick -- who is hitting .280 at Visalia, and shortstop Chris Owings.
Owings, 19 years old and also a 2009 first-rounder, was a Midwest League All-Star at South Bend last season before getting shut down with a foot injury. He is hitting .275 on the season playing alongside Borchering, with five home runs and 22 RBIs.