Call it a conspiracy theroy if you will, but my gut feeling is that Wednesday's MRI didn't show the Mets anything new about the condition of Oliver Perez's knee. It was a necessary step to avoid the appearance that they were using the disabled list as a dumping ground, but if they'd found the healthiest knee in the history of knees the end result would have been the same. Perez goes on the disabled list and everyone gets a break for a few weeks.
It seems much more likely that sometime on Monday or Tuesday, the Mets sent a message to Perez and agent Scott Boras about what they had planned for him the bullpen. Perez would appear as the long man in a blowout, perhaps he'd pick up some work if a game went deep into extra innings, but he wasn't going to be trusted with consequential innings because the Mets don't trust that he can succeed in those situations.
He could die on the vine out there as a last resort, or he could show some willingness to work on correcting what's gone wrong with his pitching. Perez's refusal to go directly to the minors is understandable, but going to the DL allows him to do rehab assignments while saving some face.
What's the difference to Perez and Boras if he's making his money anyway? Perez has been in dire straits before and, Will Carroll of Baseball Prospectus reports, didn't handle it particularly well. He went to the minors while with the Pirates, refused to work on his game and, ultimately got traded to the Mets. Carroll picks up the story (link requires a subscription) from there.
There's a lesson to learn here in that Perez did come back, but only after a trade and some work with Rick Peterson, then the pitching coach for the Mets. No one, most importantly the Mets, seems to know what the fix might be this time, or when he'll get back.
The fix might be somewhere other than Queens, which is why Boras and Perez are wise to agree to the DL plan. Perez is only 27, so he'll have another lucrative contract ahead of him if he can get back on track. Maybe that happenens with the Mets, maybe it doesn't, but some pitching coach will want a shot at straightening out a talented lefty. He needs to show he's willing to work to make that happen, though, and this is one way of doing that.