Evaluating the Adam Eaton trade

Yes, the "Adam Eaton" trade. In a three-team deal on Tuesday, the Arizona Diamondbacks sent Eaton to the Chicago White Sox, the Sox sent Hector Santiago to the Los Angeles Angels of Anaheim, who then sent Mark Trumbo to the Diamondbacks, who completed the trade by sending Tyler Skaggs to the Angels. That may have been a run-on sentence, but it gives you an idea of just how many moving parts were involved.

This looks like a very good deal for the White Sox, who acquired Eaton in exchange for Santiago. It also looks good for the Angels, who turned Trumbo into two rotation pieces. I'm less enthusiastic about the value of the trade to the Diamondbacks, who plan on playing Trumbo in the outfield.

Venerable sabermetrician Dave Cameron offered his opinion of the trade.

Steamer projects Adam Eaton for a 112 wRC+, Mark Trumbo 113. Trading Eaton for Trumbo straight up is silly, much less adding an arm.

— David Cameron (@DCameronFG) December 10, 2013

Hmm. I'm inclined to agree, but let's take a deeper look at Trumbo. First and foremost, he hits lots of home runs. In the last three years, he has 95 long balls, which is exactly as many as Giancarlo Stanton. He also plays pretty good defense at first base, as shown by a career UZR/150 of 8.8.

But, there is a gaping hole in Trumbo's game—namely, his plate discipline.

Trumbo owns a career on-base percentage of .299. Here are some first basemen with a lower on-base percentage. Oops, there actually aren't any. Out of 287 qualified hitters going back to 2010, only 11 have a higher O-Swing% than Trumbo's 39.0 percent. Even J.P. Arencibia has a lower chase rate. His swinging strike rate of 13.8 percent is 11th-highest among that group. The plate discipline issues have contributed to a 111 wRC+, which is just a hair better than the major league average for first basemen. The much-maligned Ike Davis, for example, has a career 112 wRC+.

Still, despite his flaws, Trumbo has averaged 2.3 fWAR the last three seasons, and Steamer projects him to do more of the same in 2014. The former Angel also has another three years of team control, with Matt Swartz of MLB Trade Rumors projecting him to earn $4.7 million in arbitration.

However, there are some troublesome facts about Trumbo that lead me to believe he may underperform his projections. His Zone-Contact rate dropped three percentage points in 2013, and his strikeout rate climbed for the second straight year. Bill Petti has found that hitters with drops in their Zone-Contact rate of at least 1.4 percent were more likely to have a collapse year than those who did not. Also, Petti has found that hitters with high O-Zone swing rates don't age very well. Here's a list of Trumbo comps I drew up:

It's not a huge sample, but with the exception of Cecil Cooper, there isn't a three-win season from those players after their age-28 season. Bat-first guys with high-strikeout totals that walk infrequently don't make good long-term bets even if they come with power.

On the other hand, Adam Eaton projects to be a solid player. He won't hit free agency until 2019. Last year, he managed just a .252/.314/.360 line with an 84 wRC+, as an elbow injury limited him to 66 games. However, he comes with a prospect pedigree and has a career .348/.450/.501 minor league line, numbers that are no doubt inflated by the PCL, but are impressive nonetheless. In addition, he struck out in just 13.5 percent of plate appearances in the minors and in just 15.5 percent of his 388 major league plate appearances.

Eaton is an excellent baserunner and a strong defender. Steamer projects him for 1.7 fWAR over 412 plate appearances, but Oliver offers a more optimistic outlook, calling for 3.6 fWAR with a more favorable defensive rating. Six years of Eaton is a good bet to provide more value than three years of Trumbo, and Eaton doesn't even hit arbitration for two more years.

And, let's not forget that the Diamondbacks gave up Skaggs, who MLB.com rated as the 10th-best prospect in baseball prior to the 2013 season. His big league results aren't too impressive, but Skaggs won't turn 23 until next season. He's managed to miss bats with a 9.3 percent swinging-strike rate, and his minor league numbers are very good. Understandably, there's concern about a guy who's fastball sits around 89-91, but the Diamondbacks sold very low on a former top prospect.

Finally, Santiago is a decent pickup for the Angels. He has control issues that will likely persist given his minor league track record and reliance on the screwball. But, he owns a 22.2 percent strikeout rate, and the Angels starting rotation had just a 17.6 percent strikeout rate that was 23rd in the big leagues. Add in the favorable pitching conditions in LA's ballpark, and Santiago could be a useful piece in that Angels rotation.

From a White Sox perspective, though, turning Santiago into Eaton has to be seen as a major plus for Chicago.

In conclusion, this deal looks very nice if you're a White Sox fan, and it's pretty cool if you're an Angels fan. If you're a Diamondbacks fan well—it's just another strange offseason. At least they haven't signed Jason Kubel this year.

Yet.

All statistics courtesy of FanGraphs.

Chris Moran is a former college baseball player and current law student at Washington University in St. Louis. He's also an assistant baseball coach for the baseball team at Wash U. In addition to Beyond The Box Score, he contributes at Prospect Insider and DRaysBay. He went to his first baseball game at age two. Follow him on Twitter @hangingslurves

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