Wade Miley: mid-rotation starter with room to grow

Yesterday was a huge day for the Boston Red Sox. Fans woke up to see that the Red Sox had acquired Wade Miley, then saw the Sox add both Rick Porcello and Justin Masterson over the course of the day. While all of those pitchers slot into the middle and back of Boston’s rotation; however, the Miley trade has a good shot to separate itself as the most valuable acquisition for both the present and future of the Red Sox.

Wade Miley jumped onto the scene in 2012 when he finished the season as the runner-up for the National League’s Rookie of the Year Award in a season which saw him go 16-11 with a 3.33 ERA and 3.15 FIP for the Diamondbacks. He followed that initial season with a similarly solid 2013 season, where his ERA rose slightly to 3.55 and his peripherals took a slight hit with his FIP rising considerably to 3.98 due to a higher walk rate. However, while each of those first two seasons portrayed Miley as a solid number three starter, his 2014 season was a disappointment.

Miley’s ERA spiked to 4.34, portraying Miley as more back-end rotation filler than as a former Rookie of the Year candidate. Still, there’s reason to believe that Miley can rediscover his 2012-2013 success and perhaps even improve upon it with a fresh start in Boston.

The most prominent reason to expect improvement from Miley is that his 2014 season is likely an anomaly from the start. Despite his ERA rising nearly a full run from his 2013 season, his FIP of 3.98 was identical to the previous season’s. And while some of his failure can certainly be attributed to a rising walk rate, which has grown from 1.7 in 2012, to 2.9 in 2013, to 3.4 in 2014, Miley has made up for that increase in walks with a parallel increase in strikeouts (Miley’s 8.2 K/9 in 2014 was a career-best), which actually improved his K/BB from 2.23 to 2.44, and ground balls (Miley has induced grounders at rates of 52.0% and 51.1% the past two seasons versus just 43.3% his rookie year).

It’s also worth noting that Miley was achieving that impressive ground ball rate in front of one of baseball’s worst infield defenses last season. Moving to the Red Sox, who have an infield comprised of three well above-average defenders in Mike Napoli, Dustin Pedroia, and Pablo Sandoval as well as Xander Bogaerts, who should develop into at least a passable defensive shortstop before long, it’s easy to see Miley’s ERA moving down at least to where ERA predictors such as FIP place him.

So, if Miley is able to keep inducing ground balls at a high rate as well as continuing to improve his strikeout rate, which is strongly correlated with increased usage of his quality slider, then he ought to be a valuable addition to the Red Sox. In addition, Miley is a workhorse who has thrown 200-plus innings in each of the last two seasons.

Miley won’t serve as the Red Sox’ ace next year or probably ever, but a left-hander who can be counted on for 200 innings with an ERA around or under 4.00 has tons of value. Plus, one of Miley’s most attractive qualities is that he still has three seasons of team control remaining before becoming a free agent and those seasons will represent Miley’s prime from ages 28-30. This makes him likely to be a piece of Boston’s future much more than his fellow acquisitions in Porcello and Masterson and makes him well worth the modest price of Rubby De La Rosa, Allen Webster, and an unnamed (likely insignificant) prospect.