Bold Prediction: Ryan Dempster is Worthless

I love coming up with bold predictions. Not those off the wall ones that have like a 1% chance of happening, but those that have been built upon a shred of reality and have a reasonable chance (say 20%) of coming true. It is especially fun when everyone is either optimistic or pessimistic about a player and you’re prediction argues the opposite of the crowd. I am guessing that this particular prediction doesn’t quite sit at that level though, but I would say it is still pretty bold nonetheless. As a result of being traded to the Rangers, Ryan Dempster will be worthless in standard 12-team mixed leagues the rest of the season.

Let’s start out by talking about what he has done for the Cubs so far this year. First off, his K% is down this year and at its lowest rate since 2007, his last year as a reliever. Although his SwStk% has improved from last season’s career low mark, it still sits well below what he had posted in previous seasons. So basically, it validates the drop in strikeout rate. Also likely hampering his ability to punch batters out is a loss of fastball velocity. He is averaging below 90.0 miles per hour for the first time in his career and it represents a nearly 1.0 mile per hour drop from last year, which itself was down from 2010. This all makes it unlikely that Dempster was going to see any kind of rebound in strikeout rate over the rest of the season.

Next, his ground ball rate sits at an all-time low, as he has essentially swapped them for line drives. Obviously, that is not a good trade-off. His LD% sits at a career high 24.4%, so it would seem like hitters are teeing off on him. Yet amazingly, his BABIP is actually lower than his line drive rate, something you rarely see! If he’s not inducing pop-ups or an extreme number of fly balls, how exactly has he managed to maintain a .242 BABIP? Beats me! So that magic act he is pulling with his BABIP is going to end and bring down his career best LOB% along with it.

When you put his entire skill set together, you’re left with a 3.84 SIERA, nearly identical to what he’s done every year since he’s returned to the rotation. His luck has bounced all over the place though as his ERA has ranged from this season’s current 2.25 mark all the way up to last year’s 4.80. While we can say last year was probably just some terrible fortune, this year seems to be the exact opposite. So, even if he were to stay in Chicago, the final two months may have been very unkind to Dempster.

Now he moves to the American League, and as we know, that will reduce a pitcher’s strikeout rate and increase his ERA on average. If that’s not scary enough, he’s now calling the AL’s best hitter’s park home. Over the last three years, Rangers Ballpark has inflated run scoring by 19%, right-handed home runs by 23% and left-handed home runs by 31%. Wrigley Field of course is a hitter’s park as well, but not to the same degree as the bandbox in Texas. Wrigley has increased run scoring by a more modest 8%, been neutral for right-handed homers and boosted lefty home runs by 11%.

According to UZR/150, the Rangers defense is rated just ahead of the Cubs, but Dempster is going to see a BABIP regression regardless. So the bottom line is that even if he had stayed a Cub, the warning signs abounded. Now when you combine the regression he should have already been expected to experience in ERA with the unfavorable changes in league and home ball park, you have the potential for a massive rest of season disappointment. Unless he gets fantastic run support (which admittedly may very well happen) leading to a bunch of lucky wins, he may be very close to being worthless in mixed leagues.

Print This Post

Mike Podhorzer is the 2015 Fantasy Sports Writers Association Baseball Writer of the Year. He produces player projections using his own forecasting system and is the author of the eBook Projecting X 2.0: How to Forecast Baseball Player Performance, which teaches you how to project players yourself. His projections helped him win the inaugural 2013 Tout Wars mixed draft league. He also sells beautiful photos through his online gallery, Pod's Pics. Follow Mike on Twitter @MikePodhorzer and contact him via email.

Sort by:   newest | oldest | most voted

You’re absolutely right that Dempster’s numbers point to regression no matter where he pitches from.

That said, I did some more specific home vs. away park analysis yesterday, and am not so sure that his move to Arlington is anywhere near as bad as people think it will be. My main concern was the amount of influence Rangers batters had on the park factors at Arlington, figuring that one of the most potent offensive lineups in baseball would be better able to take advantage of any benefits their home field advantage provided them more so than a visiting lineup, thus magnifying the overall hitters advantage beyond how it actually affects Rangers pitchers (but absolutely relevant to visiting pitchers). Basically, I wanted to ignore the Rangers offense altogether.

For my purposes, I used RA rather than ERA (same thing, using all runs rather than just earned runs), as I’m more concerned with the amount of success visiting offenses will have, earned or not (incidentally, this will be worse for Texas, who are tied for 6th in the MLB for giving up unearned runs, than for the Cubs, who are tied for 24th). I also looked at HR/9. All numbers are for 2012 through Tuesday.

Obviously you are correct that AL pitchers allow more runs than NL pitchers. Specifically home park RA averages to 4.27 in the AL, 4.12 in the NL. The AL also allows 1.02 HR/9 at home vs. .98 in the NL. These differences are slight enough that (without deeper analysis) I think they can be accounted for completely by the DH. It also shows that simply a move to the AL should not, in and of itself, cause more than a minor difference in a pitcher’s value (again, absent deeper analysis into a specific pitchers makeup and any differences in the makeup of the offense they’ll be facing).

Texas’ home RA is 4.49. That’s good enough for .22 runs/9 worse than AL average, which puts them better than Chicago, Toronto, Baltimore, Boston, Kansas City, and AL worst Minnesota. But that’s not even half the story.

Texas’ home RA is .44 higher at home than on the road, one of 6 AL teams who have a worse home RA than road RA. That list breaks down as follows: Boston [+.84], Chicago [+.79], Baltimore [+.65], Texas [+.44], Kansas City [+.40], Yankees [+.09]… so the Rangers’ pitchers are good for an extra half a run at home, but there’s 3 AL parks that hurt their pitcher’s more. But what’s more telling is this: The overall run difference is only 7th in the AL, accounting for home team advantage (meaning, on average pitchers do better at home, I’m taking the difference from the average, not from 0). 7 Team parks are more neutral for their pitchers, 6 parks are more extreme (either for or against their staff).

HR/9 is where things really go cockeyed: Texas pitchers give up 1.05 HR/9 at home, good for .03 more than AL average, but that puts them ahead of the Yankees, Red Sox, Twins, White Sox, Blue Jays, and Orioles. All of those teams give up more HR/9 at home than the Rangers pitchers do. Not only that, but Rangers pitchers give up .01 *less* HR/9 at home than they do on the road. Clearly home field advantage for Rangers batters is a large factor in the typically measured boost to HR that is talked about so much in Arlington. This puts them as the *most neutral ballpark in the AL for home pitchers* for giving up HR.

Not exactly the extreme hitters haven for visiting batters we’ve been hearing about. But, there’s still the direct difference between being a home pitcher at Wrigley and a home pitcher at Arlington to look at, even though the conclusions will be far less reliable (which are probably not as general as implied to begin with).

Cubs pitchers have been a full run/9 better at home than they were on the road, and are .45 runs/9 better than Texas pitchers at home. But wait. Cubs pitchers are 4.04 RA at home, Texas pitchers are 4.05 RA on the road. Cubs pitchers are 5.04 RA on the road, Texas pitchers are 4.49 at home. Looking better for Texas than ChC there. HR/9 looks much better for the Cubs, where they only give up 1.03 HR/9 at home and .95 on the road, better in both cases than the Rangers.

Obviously this is only a small part of the picture when it comes to the differences Dempster is going to face, but one which I’ve never seen looked at before. Odds are what will happen is that he’ll regress according to his peripherals a little bit, he’ll experience a little bit more challenge from the DH, and the results we see will be totally attributed to pitching in Arlington. I’ll be curious to look at his home/road splits.