The Giants still need salary cap space, the 10-year veteran offensive lineman is entering the final year of his contract, and releasing him would save the Giants his $4.475 million base salary against the cap.
On top of all of that, Giants' fans love to go on and on about how awful Diehl is. About how he really can't play no matter what position he plays on the line. About how his Pro Football Focus scores are almost always horrific.
Diehl might yet get released before free agency starts, or at least have his contract restructured to give the Giants some cap relief.
Thing is, like it or not there is a legitimate reason why the Giants could want to keep the 32-year-old around. You can sum that argument up in one word -- versatility.
During his career Diehl has started a significant number of games at every position on the offensive line except center. Argue all you want about his effectiveness, or lack thereof, at any of those positions. Where else, though, are the Giants going to find a lineman able -- and willing -- to shuffle to any position on the line at any time with little or no notice. Especially one who already has familiarity with the offense and the linemen he would be working with? Nowhere. That versatility and unselfishness makes an impression on a coaching staff and general manager.
The Giants have question marks all across their line right now.
Left tackle Will Beatty is a free agent. Odds are the Giants will re-sign Beatty, but until you know for sure maybe cutting loose a potential replacement (and I know Diehl at left tackle makes you cringe) isn't the smartest idea.
Left guard Kevin Boothe is also a free agent. Who knows what happens there, but again having Diehl on the roster could soften the blow if Boothe leaves.
Center David Baas and right guard Chris Snee are both recuperating from off-season surgeries. Both should be fine, but again until you know for sure do you really want to limit your replacement options?
At right tackle, without Diehl right now there are only question marks. Can James Brewer, or maybe Brandon Mosley, do the job? Can Sean Locklear return from knee sugery to be, at least, a backup? Will the Giants even re-sign Locklear?
It is entirely possible, of course, that despite these questions the Giants will decide they need the cap space and that moving in another direction is the right thing to do.
It's also possible, though, that Diehl could still be a Giant in 2013.