Doug Fister Is Starting to Look Like Mike Mussina

When Doug Fister broke into the big leagues, he was a soft-tossing, pitch-to-contact change-up artist, who threw strikes with mediocre stuff and projected as a back-of-the-rotation innings eater or a bullpen guy. He wasn’t bad, but the lack of a quality breaking ball and his reliance on his change as an out-pitch meant that he didn’t have anything to strike out right-handed batters with, and he wasn’t generating as many groundballs as you’d expect from a 6’8 guy with good command. Over his first year and change in the big leagues in 2009-2010, he was basically the definition of average, running a 102 ERA-/99 FIP-/99 xFIP- in 232 innings. He limited walks and avoided home runs, so he looked like any member of the Twins rotation over the prior 10 years. Nothing wrong with that, but certainly not a lot of upside beyond strike-throwing middle-of-the-rotation guy.

Then, last year, Fister began to change. His velocity picked up, and instead of topping out at 91-92, he started hitting 93-94 with regularity. By the end of 2011, his average fastball was over 90 mph, up two full ticks over his 2010 average. At the same time, he began to rely less on his fastball/change-up combo, and increased his breaking ball usage, especially against right-handed batters. The increased velocity and pitch mix led to a spike in his strikeout rate, which jumped from 12.9% to 16.7%. In fact, he ended the year with a 28% strikeout rate in September, looking nothing like the pitch-to-contact guy who showed up a few years earlier.

This year, the velocity has regressed back to previous norms — perhaps due to a costochondral strain that landed him on the DL twice — but the strikeout rate has still taken yet another leap forward. Once again, Fister has reduced his reliance on his fastball, and now he’s featuring his curve ball more than ever before. In his start against the Yankees yesterday, he snapped 25 curveballs, 15 of which went for strikes. This big bending curve has now become his #2 pitch, and its effectiveness has been the driving force beyond his second drastic increase in strikeout rate.

Since he doesn’t throw it much when he’s behind in the count (only 10% of the time with no strikes), we expect it to be a positive outcome pitch simply because of the times he’s choosing to use it. However, even adjusting for the counts he’s throwing it in, his curveball has become extremely effective. 12-6 curves are generally known for freezing hitters, and Fister’s is no exception – opposing batters only swing at 35.2% of his curveballs, even though he’s primarily throwing them when he’s ahead in the count. This isn’t because Fister’s burying it in the dirt, either – his Zone% on curveballs is 48.9%. And when opposing batters do swing at the curve, they whiff 11.9% of the time, and even when they manage to put it in play, the curve has generated 53.8% ground balls.

Basically, Fister’s curve is a pitch that gets called strikes, swinging strikes, and ground balls. He can locate in the strike zone or put it in the dirt, and he varies his locations enough that opposing batters haven’t been able to adjust. This addition of a legitimate out-pitch breaking ball has given Fister another weapon, and one that works against hitters from both sides of the plate.

The results have been tremendous. Over the past calendar year, Fister has thrown 167 innings at premium ace level. His line over the last 365 days:

3.9% BB%, 21.8% K%, 50.4% GB%, .281 BABIP, 10.4% HR/FB, 66 ERA-/69 FIP-/71 xFIP-

That’s a 5.6 K/BB ratio while getting ground balls on half of his balls in play. How impressive is that? Here’s the pitching leaderboard, sorted by xFIP-, over the past calendar year.

1. Stephen Strasburg, 68 xFIP-
2. Doug Fister, 71 xFIP-
3. CC Sabathia, 74 xFIP-
4. Zack Greinke, 75 xFIP-
5. Cliff Lee, 76 xFIP-

Prefer non-normalized home run rates? That’s okay, Strasburg is still the only guy ahead of Fister by FIP-, but instead of having second to himself, he falls into a three way tie with Chris Sale and Clayton Kershaw. Not bad company, I don’t think. Don’t want to judge by peripherals, and would rather just look at run prevention instead? Okay, fine, he falls all the way to sixth, behind Kershaw, Justin Verlander, Sale, David Price, and Jordan Zimmermann.

For the last year, Fister has been one of the elite pitchers in baseball. While his prior history suggests that we expect some regression, a look at Mike Mussina’s career shows that there’s precedence for this kind of career trajectory.

Through age 25, Mussina had very similar walk and strikeout rates to Fister, as he was always a pitch-to-contact strike-thrower. He had significantly more success from a results standpoint, as he was essentially the Matt Cain of his time, limiting hits on balls in play in his first five big league seasons. But, starting in his age 26 season, his strikeout rate took a big jump, just like Fister’s has.

Source: FanGraphs — Mike Mussina, Doug Fister

Over a four year span, Mussina’s strikeout rate jumped from 14% to 18% to 20% to 24% before settling in around 20%, where he would spend most of the rest of his career. Like Fister, Mussina was not a big time power pitcher, but he featured a top shelf curveball, a really good change-up, and elite command. Once he made the switch from hit preventer to strikeout collector, he never went back, and he had a long run as one of the best pitchers in baseball.

Fister’s only had one year at this level, so I’m not endorsing his Hall of Fame candidacy, but it is worth recognizing that Fister is following the same basic career evolution that Mussina took. The addition of an effective 12-6 curve has taken him out of the pitch-to-contact playbook, and now Fister is simply pitching like a strike-throwing ace.

Can he keep this up? It basically comes down to the strikeouts. We know he can throw strikes and we know he can get ground balls. If his strikeout surge is something he can sustain, then there’s no reason Fister can’t keep pitching at an elite level. We need to see more than 170 innings of excellence before we can put Fister in that kind of consistent ace category, but he’s on the right path. For the last year, Fister has been as good as anyone in baseball, and he’s making adjustments that look like they may help keep him there. If he does keep racking up the strikeouts, acquiring Fister for a pu-pu platter of role players may end up being one of the great steals in baseball history.