John Danks: The Left-Handed Edwin Jackson

With a relatively weak free agent pitching market, more and more teams are turning to the trade market to try and upgrade their rotations this winter. The White Sox have taken note of this shortage and inserted themselves as sellers of pitching, and are rumored to be taking offers for both Gavin Floyd and John Danks. With Kenny Williams talking about rebuilding, moving one or both could make some sense, as Danks is a free agent after the 2012 season and Floyd is only under team control for two more seasons.

Despite being under contract for one fewer year, however, Danks has proven to be the hot name on the market over the last week. Jon Paul Morosi reported that the Rangers are interested in a reunion, which Jon Heyman also reported and noted that Danks would be “very popular”. On Saturday, Keith Law tweeted that he thought Danks would get more than C.J. Wilson if he was a free agent this winter.

Clearly, Danks’ skillset as a quality young pitcher is in demand, and it seems likely that someone will pay a significant price to acquire his services for 2012. However, I’d like to suggest that if someone wants the package that Danks can bring to the table, they could save themselves the hassle of giving up talent and just sign Edwin Jackson instead.

I know that on the surface, they don’t seem all that similar. Danks is a lefty, Jackson is a righty. Jackson is a power pitcher whose fastball sits around 94 and throws a lot of sliders. Danks’ velocity is several ticks lower, he leans on a cutter as his main secondary pitch, and he throws a lot more change-ups. But, look at their performances over the last three seasons – the two have produced remarkably similar results.

Name	BB%	K%	GB%	ERA-	FIP-	xFIP-
Edwin Jackson	7.9	18.5	44.0	93	92	95
John Danks	7.7	18.2	44.5	90	92	96

In terms of core skills, it’s nearly impossible to find two pitchers with more even numbers over a three year period of time. Their walk rates, strikeout rates, and ground ball rates are nearly identical, and even numbers that come with more external variance – HR/FB rate and LOB%, for instance – are alost exactly the same. Danks has Jackson beat on BABIP, but even that ability to limit hits on balls in play has had a minimal effect on their overall outcomes, as Danks’ 90 ERA- is just marginally better than Jackson’s 93 ERA- over the same time period. Toss in the fact that Jackson has thrown 40 more innings over the last three years, and that small difference essentially evaporates – these two have essentially pitched to a draw since the start of the 2009 season.

So, why is the perception of Danks so much more positive than the perception of Jackson? Their early career performances probably dictate most of that.

Jackson came up as a much-hyped 19-year-old with the Dodgers in 2003, but outside of one pretty great start in his Major League Debut, he wasn’t very good. After a few seasons of disappointment, the Dodgers shipped him to Tampa Bay, where he continued to not be very good. Even during his “breakout” year of 2008, his xFIP was 16 percent worse than league average. For the five years following his debut, Jackson was pretty lousy, and earned the reputation as a guy who simply couldn’t get his results to match his considerable stuff.

That reputation has never really gone away, even as Jackson has developed into an above average innings eater over the last few years. Because his improvement has been more incremental that drastic, he’s never shaken the reputation of a guy with good stuff and poor command, despite the fact that his walk rate is slightly better than league average nowadays.

Meanwhile, Danks’ early career reputation is completely different. He struggled with a home run problem in his rookie season at age 22, but in his second year in the big leagues, Danks was terrific – he upped his ground ball rate significantly, cut his walks, increased his strikeout rate, and saw his ERA fall from 5.50 to 3.32. At just 23-years-old, he finished 5th in the league in ERA, and quickly came to be seen as one of the game’s best young southpaws.

The fact that his peripherals didn’t support that kind of low ERA was mostly overlooked, however, and Danks’ performance the last three seasons have served to re-establish the idea – founded in 2008 – that he’s a high-quality starting pitcher. Because the perception of Danks going into the last three years was positive, his performance is seen in a different light than Jackson’s. Instead of being judged on what they’ve done more recently, both pitchers are still being judged by reputations that were built off performances from four years ago.

We shouldn’t ignore the early career performances of both pitchers, but history has shown that data beyond the most recent three years isn’t that useful in helping project future performance. We also need to be cognizant of the fact that Jackson debuted at a very young age and simply wasn’t ready to pitch in the big leagues, so while he has a much longer track record of failure, Danks’ Major League resume doesn’t include what he was at age 20 or 21, and if he had been pushed as quickly as Jackson has, he’d likely have quite a bit more failure in his past as well.

The reality of the two pitchers is that they’re both young-ish arms (Jackson is 28, Danks will turn 27 in April of next year) who have performed at nearly the exact same level over the past three seasons. In projecting future performance, it’s extremely difficult to make a case that Danks will be substantially better than Jackson, and there certainly isn’t enough evidence to suggest that a team should be willing to surrender premium talent in order to acquire Danks in a trade when they could sign just Jackson as a free agent instead.

For a team looking to upgrade their rotation, Danks could be a very useful piece. I’d just suggest that, before they give up a premium prospect to acquire one year of his services, that they check in on the cost of signing Jackson instead – they might very well get a similar pitcher at a similar cost without having to surrender any talent to acquire him in the first place.