Peter G. Aiken-USA TODAY Sports
2013 Stats (AA/AAA): 100 IP, 2.16 ERA, .193 BAA, 112/35 K/BB (17 GS)
Selected by the Mariners in the supplemental first round of the 2010 draft, Walker has everything you want in a future ace. At 6’4”, 210 pounds, the right-hander is an outstanding athlete with a fluid delivery, quick arm and exceptional stuff.
After a strong showing at Low-A Clinton in 2011, the Mariners aggressively bumped Walker to Double-A—bypassing the High-A level—to begin the following season. As expected, the then-19-year-old showed flashes of brilliance but struggled with his command and execution. However, the lessons he learned last year as a younger player at an advanced level were crucial to his overall development.
Assigned back to Double-A Jackson to begin the 2013 season, Walker has quickly evolved into the pitcher everyone knew he’d become. Through his first 14 starts, the right-hander registered a 2.46 ERA and .195 BAA with 96/30 K/BB in 84 innings, and ultimately forced a promotion to Triple-A. And in his first three starts at the new level, the 20-year-old allowed one earned run while striking out 16 batters in 16 innings.
Walker boasts a plus-plus fastball that reaches the upper-90s, and he has also developed a high-80s/low-90s cutter that should be at least above-average at maturity. Although his command of both pitches has vastly improved this season, he still tends to leave too many up in the zone—something that will be exploited at the next level.
Both of Walker’s secondary offerings are also in need of refinement. The right-hander induces whiffs with a curveball that has big-time depth and heavy downer action, though his lack of control makes it an inconsistent offering. Meanwhile, he’s still developing a feel for a changeup that’s average at the moment but plays up when he’s working the corners with the fastball and cutter.
Given his success and overall maturation from a thrower to a pitcher this season, it seems increasingly likely that Walker will receive his first taste of the major leagues later this season. The organization doesn’t need to overexpose him in the Pacific Coast League, and more importantly, a promotion in September represents the next logical step in his development. And while I don’t expect him to open the 2014 season in the starting rotation, the right-hander should at least spend several months in the major leagues.