Giving Mike Dunn his due


I’ve paid a lot of attention to Omar Infante as part of the recent Dan Uggla trade, but I am almost certain that the Marlins brass coveted a pitcher more than they did a year of Infante playing for the Marlins. Indeed, during the negotiations, it was said that the Marlins returned during the GM meetings asking for a pitcher in addition to Infante in order to complete the Uggla deal. So it wouldn’t surprise anyone to think that Mike Dunn, a reliever originally acquired by the Atlanta Braves as part of the Javier Vazquez package, was actually the most important part of this deal.

I never liked deals involving relievers who weren’t top notch to begin with. Dunn is young and has a live arm, but he has some definite issues, and there’s a question as to whether the Marlins couldn’t at least pick up someone who could start. But since the Fish were so interested in him for this trade, I figured it would be worth our time to give him his due and take a look at how he should perform in the future.

Toolset and Stat History

Dunn has all the makings of a classic power arm. He averaged 94.5 MPH on his fastball in his brief 23 innings in the majors, and he’s always been known to have that kind of strength. He is a lefty, and as such will remain extremely valuable with that kind of velocity. Along with that fastball, Dunn has a slider but not much of any other offerings. A converted outfielder, Dunn has only been pitching primarily in the big leagues, which is surprising given how well he has taken to the position.

Here’s what John Sickels had to say about him in his 2010 review article:

"16) Michael Dunn, LHP, Grade C+: 1.05 ERA, 56/22 K/BB in 43 innings for Gwinnett, 26 hits. Has pitched 4.1 scoreless major league innings. Looks like he’ll be a nice bullpen contributor though walk rate remains troublesome."

That’s basically been the rap on Dunn throughout his relieving career. After shifting to the bullpen, he began losing all semblance of control, walking hitters at a huge rate. Look at his 2009 and 2010 in the minors, splitting time between Double- and Triple-A.

2009, Double-A Trenton: 53 1/3 IP, 3.71 ERA, 76 K, 32 BB, 4 HR
2009, Triple-A Scranton/Wilkes-Barre: 20 IP, 2.25 ERA, 23 K, 14 BB, 1 HR
2010, Triple-A Gwinnett: 47 1/3 IP, 1.52 ERA, 64 K, 25 BB, 1 HR

Those strikeout numbers are indeed staggering, but the walks are going to be very limiting, especially as he moves into a major league role. My guess is that those impressive numbers are in part due to his overpowering fastball; minor league hitters can be outdone by just dominating stuff, even with a lack of control. Major league hitters, on the other hand, are not so easy to beat. So far in his major league career, he has had a huge 20.4% BB% (!) while accompanying that with a 29.6% K%.

As you can see by the low home run totals, Dunn has never given up the long ball at a high rate. As a reliever for two seasons between two levels, he has only allowed five homers in 527 batters faced, a miniscule 0.9% mark. However, I think that again has something to do with how overpowering he can be with his stuff and the quality of minor league hitting that he was seeing. Major league hitters should have an easier time knocking Dunn’s offerings out of the park, though they may still do it at a below average rate. Not helping matters is the fact that, as a reliever, Dunn was never the type of guy who forced a lot of ground balls. Combining both his major and minor league numbers from 2009-2010, he has only induced grounders on 39.5% of his balls in play, a very low number indicative of a player who does not possess the sort of sinking stuff that should keep balls in the park more consistently.


CHONE had Dunn as a true talent 4.17 ERA pitcher in a neutral context, as of the latest update in late August. Dunn was projected to strike out 9.65 batters per nine innings but also walk 5.56 batters, which is in line with what he did in the minor leagues. The home run rate of 0.81 per nine innings seems fair, given the likelihood of relievers allowing fewer homers as part of the advantage of relief pitching and the fact that Dunn historically has not allowed a lot of homers. Still, a 4.17 ERA is not an impressive feat for a reliever. A pitcher with a true-talent rate of 4.53 runs per nine innings in an environment that scores just around that many runs (I have next year’s environment at 4.51 runs based on a three-year weighted average) would be just barely above replacement for a reliever.

Giving Dunn 60 innings of work this season with that projected ERA/RA and an average leverage index of 1.1, I get Dunn’s contribution this year as 0.2 WAR. That’s not great, but it’s certainly worth more than the rookie minimum, so the Marlins cannot complain. More importantly, how much can the Marlins expect to get out of Dunn over his team-controlled time period? We’re squabbling about fractions of a win here, but giving Dunn 0.5 WAR over the next four seasons and 0.5 WAR for his last two years combined, you get a value of about $11M and change. If Dunn picks up $6M in total for three arbitration seasons and the Marlins get him for six seasons in total, you might expect a surplus value of about $1M.

While that estimate is probably fair, it is still highly volatile due to the nature of relievers. Dunn could flame out this year and next and never see the light of day in the majors again (see Taylor Tankersley). Or he could magically figure everything out and become a left-handed Jonathan Broxton. This is part of the reason why I did not like the idea of requiring a reliever as part of a package for our prime trading asset of this offseason; you just never know what you’ll get out of them in the future. The Marlins are gambling on Dunn’s live arm, and hopefully the gamble pays off. As of now, that Uggla trade still seems to fall short.