As has been broken now by a pair of sources (SLU Baseball, Nick Piecoro) - though with no official word from the team - the Arizona Diamondbacks plan to call up LHP Wade Miley from Triple-A Reno to replace RHP Jason Marquis in the D-backs starting rotation. Miley will presumably make his debut with the D-backs on Saturday against the Atlanta Braves. Initially drafted by the Tampa Bay Rays in the 20th round of the 2005 MLB Draft, Miley didn't sign and instead went to Southeastern Louisiana University, where he starred for three seasons. The choice to go to college proved to be wise, as Miley's stock soared, landing him in the Supplemental Round of the 2008 MLB Draft, when he was selected 43rd overall by the D-backs, praised for his polish, quick-rising potential, and plus slider.
Things didn't work out for Miley in the beginning, as the big left-hander struggled in his first year and a half in pro ball, looking like he was going to be a disappointing pick. He was initially assigned to Yakima in the Northwest League after signing, making just seven relief appearances before the year ended and posting a 4.91 ERA in 11 innings of work. Things started to get really worrisome, however, in his first full-season assignment. Initially sent to the pitcher-friendly Midwest League to begin the 2009 season, Miley was supposed to dominate in a league where most hitters were about a year below him in age. Unfortunately, Miley posted just a 4.12 ERA in 21 starts for the Silver Hawks, spanning 113.2 innings. The D-backs nevertheless gave Miley a promotion near the end of the season, and the lefty finished his year with the Hi-A Visalia Rawhide, posting a 4.80 ERA in 15 innings.
Things started looking up for Miley in 2010. Back at Visalia to begin the season, he struggled to post good K:BB ratios against the Cal League bats, but still had success because of an uncanny (and lucky) ability to keep the ball in the park. Miley's 3.25 ERA in 14 starts, spanning 80.1 innings on the hill, for Visalia was supported by just a 50:37 K:BB ratio, but only a single home run allowed. That was enough to get Miley promoted to Double-A Mobile halfway through the 2010 season, and that's when he really started to take off as a prospect. In 13 starts for the BayBears in 2010, Miley went 5-2 with a 1.98 ERA and 63:28 K:BB ratio in 72.2 innings, with reports coming out that Miley was sitting consistently above 90 mph and touching 96 mph, a significant spike from the upper-80's he had been generating at times in 2009.
That production skyrocketed the left-hander up D-backs prospect rankings, and Miley finished the 2010 season ranked eighth on the D-backs top-10 prospects list according to Baseball America, ranked seventh on the D-backs top-20 prospects list according to Kevin Goldstein of Baseball Prospectus, and ranked fifth on the D-backs top-20 prospects list according to John Sickels (my personal favorite pitching prospect guru). All three sources cited improving consistency, confidence, and command on the mound, as well as the velocity spike, while naming Miley as the prospect who had most improved his stock in 2010.
2011 began with Miley in major-league spring training, and he was the talk of camp for the first few weeks. This comment seems much, much less impressive in hindsight (/sarcasm), but Miley was described by Melvin Mora in this Nick Piecoro blog post as "filthy" during Spring Training. Unfortunately, shoulder woes started to seep in during the latter parts of camp, and Miley got off to a rocky start to the season with the BayBears that included a DL stint and a three-game stretch to begin May in which Miley posted a 12.64 ERA. Since that stretch, though, Miley has been phenomenal, putting his injury woes behind him and allowing just 38 runs in 106.2 innings between Mobile and Reno, a 3.21 ERA split between Double-A and an excruciatingly-difficult Triple-A league for a pitcher.
Since joining Reno, Miley has posted a 3.64 ERA in eight starts, fanning 56 with just 16 walks in 54.1 innings of work. That ERA figure is the second-best among pitchers who have started a game for the Aces this year, behind the 1.50 ERA that Josh Collmenter accumulated in his one and only Triple-A outing prior to his promotion to the major leagues. The next-best ERA among Aces starters belongs to Barry Enright, who owns a 4.84 ERA in 17 Triple-A starts, followed by Micah Owings' 4.85 ERA in seven starts prior to his big-league promotion.
Miley has a wide arsenal, touted by BA as working with a fastball, slider, curveball, change-up, and cutter. The curveball and cutter are more of show pitches, but the fastball has good zip and sink for a left-hander, coming in consistently at 92-93. Miley's slider is widely-regarded as a plus pitch that he can miss bats with, while the change-up, also "flirts with being a plus pitch," according to BA's off-season write-up. Multiple reports stated that Miley's slider occasionally gets a bit slurvy, which basically means that the typically-sharp break the pitch has as it heads towards the plate can occasionally round out, becoming more arced and transparent to batters. We'll have to see if this is still an issue, or if he has sharpened the pitch in 2011.
One red flag that has been raised has been that there is some meltdown potential in the southpaw, as he has occasionally gotten rattled on the mound, losing his mound presence, composure, and mechanics. When that happens, things can go south in a hurry. However, he is coming off of his best start as a professional, allowing just one run in a complete game effort in New Orleans, striking out nine and walking just one to beat the Zephyrs, affiliates of the Marlins. With that outing likely building confidence, I imagine now is as good a time as ever to bring the 24-year-old to the majors and see what he's made of.
I'd say that Miley's upside is around a 4.00 ERA #3 starting pitcher, although expecting that from him right out of the chute is probably a bit overly-optimistic. If he can gain consistency and stay away from the Trainer's office, he has a chance to be a fine starting pitcher.