Can Doug Fister Rebound in 2016?

Last Thursday, the Astros shook off the winter doldrums with their first meaningful move in free agency, inking 31-year old righty Doug Fister to a one-year deal. Rumored for some time to be on the hunt for a starting pitcher after bolstering the bullpen with the addition of Ken Giles, the Astros added some needed depth to the back-end of the starting five.

At best, Fister can regain some of the form that led him to a top-10 Cy Young finish in Washington two years ago, but there's obviously some injury risk to this deal. $7 million doesn't sound like a lot of money for a fifth starter until he's on the shelf for the entire season, a la Jesse Crain and Matt Albers in 2013. Though we can't know for sure if Fister will make three starts or 30 starts this season, we can make a few guesses on what kind of value he can add to the team based on his 2014 performance.

A close look at some of Fister's trends do not show his 2014 as a realistic expectation of this upcoming year. Fister posted abnormal BABIP numbers during his success that season as he earned the Nats 4.5 wins above replacement (via Baseball Reference). However, Fister showed success in earlier seasons outside of those statistical outliers, posting solid WAR totals between 2011-2013. Thats what Houston is looking for, and it doesn't hurt that Fister fits the bill of his new rotation as a low-strikeout, low average velocity, high groundball-inducing starter that can pitch to contact with great success.

The first word of caution for Fister, however, is that low velocity. For most of his career, Fister has managed to hurl a four-seamer toward home plate at roughly 88 miles per hour. That would ideally fit in with the Astros, who's starters managed an average fastball velocity of 91.2 mph last season, 25th in the MLB. This number, obviously bumped by the 29 combined starts of Lance McCullers and Vince Velasquez, didn't negatively affect the pitching performance due a vacuum of a defense and some wizardry from Brent Strom. In 2015 though, Fister's four-seam velocity dipped to a concerning levels that may spell trouble even in the Astros' low-velocity style.

Though it's documented that Fister missed time with injuries last season, this abnormal dip of four-seam velocity to 86.9 mph suggests he also pitched hurt, or for a more daunting conclusion, is losing fastball velocity as he moves past the peak of the pitcher aging curve. The two are also not mutually exclusive. The Astros made a clearer conclusion to this question than I can, but those two options are a realistic downside to Fister's potential performance this season, even on a low-risk deal.

For a little more perspective, here's another plot that includes Fister's sinker velocity against fastball velocity over his career.

Fister's fastball and sinker decline are obviously concerns; hitters square up the ball against lower-velocity fastballs, leading to faster exit velocities. For a groundball-reliant pitcher like Fister, that could spell trouble. However, if the Astros believe he's fully healthy after arm issue last season, the consequences of a declining fastball will be avoided.

A few of Fister's peripheral numbers from his excellent 2014 deserve some analysis. In 2014, Fister posted a 3.93 FIP against a 2.41 ERA, a startlingly large gap between Fister's performance and how he should've actually fared. So what exactly went into that discrepancy? Fister's batting average on balls in play can help us here.

Highlighted data point is Fister's 2014 top-10 Cy finish.

In 2014, Fister posted a career-low .262 mark, well below his career .292 BABIP. Though Fister carried two sub-.280 BABIP years in 2009 and 2011, we can disregard the 2009 debut due to his 61 inning sample size. 2011 might've actually been Fister's best season, BBWAA votes aside. In a split season between Seattle and Detroit, Fister posted a 5.1 WAR. Though the low BABIP suggests poor peripherals, his FIP that year was actually 3.02. Due to a career-best walk rate with a WHIP near 1.00, Fister avoided major BABIP regression throughout the year, but never replicated the 2.83/3.02 ERA/FIP totals over the subsequent four seasons.

Unfortunately, it may be difficult for Fister to replicate his method of offsetting batted ball luck at this point in his career. Though his walk rates should stay consistently excellent, a velocity drop will make him increasingly hittable, leading to more baserunners and eventual runners scoring with the expected BABIP regression. Hitters may be able to square up fastballs more often, taking away the minimum fastball velocity that allows major league starters to find success when pitching to contact.

To be fair, the Astros aren't asking Doug Fister be the pitcher he was in 2011 and 2014. On a short deal, Fister himself is looking to build back some value as a major league starter. Though the velocity drop and batted ball luck forecast an uphill climb for Fister to replicate his past success, soaking up innings on spot starts and long relief might be all he needs to do. Though Fangraphs' Steamer only projects Fister at 1.3 WAR, he can add more value than that if he hangs on to whatever fastball velocity is left while induce grounders at solid career rates.