Each team has their own crew in place for the purpose of investigating players' medical reports. It's difficult to know just how good or bad each teams' medical staff is, so what one organization does might not reflect what the other 29 teams might. That being said, a major red flag went up a week ago, when the Cubs pulled out of a Dan Haren trade with no reason given.
Since the price was just reliever Carlos Marmol, it was assumed that the medical reports for Haren had not come back glowing, and the Cubs pulled out to save themselves the injury headache. That's all it was, though, an assumption. Until Thursday, anyway, when David Kaplan of CSN Chicago revealed that sources had confirmed this thought:
However, a long-time AL source who has watched Haren over the past several seasons confirmed to me that medical questions were the main reason the trade fell apart, with the Cubs having serious concerns over Haren's back stiffness that sidelined him for a part of the 2012 season. Also, hip issues and a noticeable drop in his velocity that forced him to pitch differently than when he was a dominant power pitcher.
Things have to be pretty bad to back out of giving up Marmol, who has his high points thanks to strikeouts and a consistently low hit rate, but sometimes more than makes up for it ridiculously high walk rates. In 2012, Marmol gave up just 6.5 hits per nine, but still allowed 1.6 baserunners per inning, thanks to 7.3 walks per nine. Or, another way to put it, despite striking out just under 12 batters per nine, Marmol's K/BB was just 1.6. Walks are easier to deal with than a hit in many ways, but it's not as if Marmol is immune to the long ball, and since peaking in 2010, he's posted just a 104 ERA+.
Theo Epstein isn't the Cubs' GM, but he does work along with Jed Hoyer. The last time an Epstein-run team pulled out of a trade like this was a day before the 2011 July deadline, when the Red Sox backed out of a deal with the Athletics after getting a look at Rich Harden's medicals. Harden ended up having season-ending shoulder surgery before the 2012 campaign began, thanks to a shoulder capsule injury that he had amazingly been pitching through. It's unlikely Haren is about go to in for major back surgery, but Epstein has taken plenty of risks on injured players in the past. The fact that the Cubs passed up on Haren is not a positive for the now-free agent hurler.
This might hurt the market for Haren, but could benefit whoever does roll the dice on him. That is, unless his back actually is in that poor of condition. It's something to be aware of, though, if the Red Sox are no longer attached to him as a free agent. It's possible they were aware of the severity of the issues, but were willing to gamble on them anyway, especially at the cost of just Alfredo Aceves. But, maybe not, since the Angels never did find a taker after the Cubs changed their mind.
One wonders if Haren is now going to be one of the pitchers who has to wait until the rest of the market settles, like Edwin Jackson did last winter. Backs are a troublesome thing, and Haren has already seen some decline in his game. Whether it's permanent or not is up for debate, but it sounds like teams aren't willing to bet on the opposite being true.