Is Acquiring Hill Wise for the Diamondbacks?

The Diamondbacks traded Kelly Johnson to the Blue Jays on Tuesday, getting Aaron Hill and John McDonald in return. Arizona’s motives for the trade are questionable, as the deal could actually hurt their playoff odds.

Eno Sarris covered the deal from the Jays point of view, noting that free-agent-to-be Johnson will likely be used to extract compensatory draft picks this offseason. Johnson is mere percentage points from attaining Type A status — and prior to the trade, he was the highest-ranked non-Type A middle infielder. The Jays employed this tactic last season when it traded for Miguel Olivo on the day before free agency started and allowed him to walk. The Jays again are shrewdly exploiting the compensation system.

Add to that the idea that Johnson is a better player than Hill and the deal makes plenty of sense for Toronto. But does it make any sense for the Diamondbacks, who are in the thick of a divisional race?

First, a comparison of the swapped keystone cornermen. Johnson has a paltry .310 wOBA — in line with his 2009 performance — but he has sustained his power from a year ago, posting a .202 ISO with 18 home runs. Scouts have never raved about his defensive prowess, but UZR speaks kindly of his efforts over the last two seasons. He isn’t a liability on the basepaths and is generally regarded as a solid overall player. He won’t light the world on fire, but a league average player at second base is valuable. Contractually, his cost control runs out after the season as he reaches free agency.

Hill has a far worse .265 wOBA that ranked as the second worst in the American League. His power is also nonexistent, which is surprising given his ~.200 isolated power marks in each of the last two seasons. In fact, he had the ninth-worst ISO among qualifying American League players, at .088, and there is little reason to think that a change of scenery will fix the issue. His line drive rate has increased, but his batting average on balls in play has only gotten worse. Since his contact rate has also increased, it really just seems like Hill hasn’t gotten good wood on the ball for two years now.

His defense and baserunning are generally thought of positively, even if the advanced metrics don’t bear it out, but he isn’t a wunderkind in either area. From a contractual standpoint, Hill has $8 million club options for both 2012 and 2013, and he has no shot of becoming a Type A free agent if those options are declined.

All things considered, Johnson is the better player, so if the Diamondbacks saw something in Hill that led them to believe he would better aid their playoff hopes, it’s hard to figure out their vision. One possibility was that they went for Hill given his cost control over the next two seasons, and thought that their coaching could make him worth more than the annual $8 million salary. However, that doesn’t seem very plausible, as smart money would have Kevin Towers declining the options after the season. Who in their right mind would want to pay Aaron Hill $8 million per year to hover around the replacement level? Even as a 1.5-2 win player, he could likely be had for much less money on the market.

That both Hill and Johnson will likely reach free agency next season, that Johnson is clearly a superior player right now, and that Johnson will net his employer more valuable compensatory picks puts the swap firmly in favor of the Jays. Johnson wasn’t vying for the MVP Award, but Hill has shown nothing over the course of the last year and a half that he is anywhere near the player he was from 2006-09.

But the deal wasn’t just about swapping second basemen. The Diamondbacks also acquired John McDonald, a super-utility player who, unlike Willie Bloomquist, can field at an above average clip all around the diamond. McDonald can’t hit worth a lick — though he is actually posting a higher wOBA than Hill at the moment — but he gives the Diamondbacks depth at shortstop in the absence of Stephen Drew.

However, the difference between McDonald and Bloomquist is slim at most over one month, so they didn’t exactly make a splash to increase their odds of winning the division. Plus, McDonald is a free agent after the season who, per the presser, fully intends to return to the Blue Jays if given the opportunity.

On the surface, this deal seems completely about the 2011 season, and under that guise it makes very little sense for the Diamondbacks. They downgraded at second base in a more significant way than they upgraded at shortstop, and potentially lost out on better compensation picks in the process. This is a head-scratcher.