On November 19, 2006, Alfonso Soriano signed the 5th-largest contract in Major League History (to that point, by total dollars). Coming off a season in which the Fonz hit .277/.351/.560 and joined the 40/40 club, the deal looked like a pretty good sized overpay, but the cost of doing business with a premier free agent (and no mistake, averaging 36 homers and 41 doubles a year to that point in your career is valuable no matter how few walks you might draw). I'm not sure anyone thought he'd live up to that contract the day it was signed, but he'd be valuable nonetheless…
At first, the contract did not look all that terrible. In 2007, Soriano would have long dry-spells where he'd swing at pitches that hadn't even been thrown yet, or pick off attempts to first. Other weeks, though, he'd single-handedly win you 2 or 3 games. He was a boom or bust player, with just enough booms to live by.
Then, 2008 happened and everything (sort-of) changed.
Soriano lost another step to another injury. The hop that was endearing to some at first quickly became "how could you not catch that fly ball?" Soriano missed 53 games, and while his numbers were essentially unchanged, people started railing on the leftfielder. It didn't help that he now made 14 million, and was about to make 17.
2009 was, simply, a disaster. Soriano missed another 45 games and played the rest of the season hurt. His numbers plummeted to .241/.303/.423 off of a .279 BABIP. The times were rare that anyone did anything but boo Soriano.
After 2009, though, Soriano has quietly been pretty productive. Even his 2011 season (.244/.289/.469) wasn't a killer (if not exactly what you want from your LF). I can't begrudge anyone for signing the contract that's put in front of them; take the money out of it and Soriano has been a pretty good leftfielder for the past 6 years, with some definite bumps in the road.
Soriano is what you would call a "free swinger." He strikes out a lot, and doesn't walk a lot (premium analysis from the new guy). Most of his offensive value is derived from his huge ISO numbers: he was 6th in the league out of qualified leftfielders, and that was the primary driver of his .350 wOBA last year (good for 11th out of qualified LF). A 7.2% walk rate isn't pretty, but keep in mind the league average last year was only 8.0% and he still exceeded the league average in OBP last year (though it was essentially a tie).
To get a better idea of how much Soriano hates to leave the bat on his shoulder, consider the fact that he swung at 36.6% of pitches out of the zone last year, according to PITCH f/x. That was 7.6% more than the league average and 7.3% LESS than his percentage of pitches he swung at outside the zone last year. Predictably, he does not make contact with those pitches and never has; his contact rates are poor even looking at only pitches in the zone. Soriano averages 13.9% swinging strikes in his career; that's 7th most in baseball, along luminaries such as Delmon Young and Josh Hamilton.
As Soriano ages, his speed has regressed considerably, and that part of his game has essentially vanished, but an encouraging trend is his relatively static BABIP. As his speed regresses, you'd expect his BABIP to fall too; it hasn't, and that's most likely because Soriano isn't getting cheap hits (and never really was). As long as Soriano's power continues to hold up (and his HR/FB% rate was pretty high last year, something to look at), Soriano should keep most of his value.
Soriano's defense is the subject of a ton of debate. I can physically see why people hate Soriano's defense in left. He looks slow, and his stride has never been elegant even when he was very fast. He also does that weird hop thing from time to time. However, Soriano has a perfectly average arm at this point, and UZR has loved his outfield range forever (cue the UZR is bullshit chants). I'm not sure how dWAR is measured, but I also am pretty dubious that Darwin Barney is Brooks Robinson reincarnate so I'm inclined to think that it's a ways off in it's estimate of Soriano. I think the truth is that Soriano is a perfectly average defender and that Sveum (or whoever did defensive alignments in 2012) is a very good manager. That being said, seeing Soriano in 2 years in left is almost certainly going to remind me of Barry Bonds (without the offense, unfortunately).
Soriano has value to a lot of teams, including the Cubs. That contract that Hendry gave to him (and let's not forget that Soriano was a part of two divisional champions in the beginning of that contract) is a sunk cost; we can only recoup whatever we don't eat in a trade. If you forget about the contract and market Soriano as a 2/$10 guy, he has a good chunk or surplus value.
Please forward this article to the Phillies.