Safe to say the theme of the 2009 Patriots defensive line could be summed up in one word: surprises.

Let's start with the obvious. New England's trade of perennial Pro Bowler Richard Seymourto the Oakland Raiders was a stunner, from which the remaining members of the defense never seemed to recover fully.

Another eyebrow-raiser was Vince Wilfork– his contract status, to be precise. While the nose tackle was having yet another Pro Bowl season (his second) in the final year of his original contract, he and the team didn't make any progress toward agreeing to an extension, while several other reserve players did ink extensions, according to media reports.

Then there were the rookies. Second-round pick Ron Bracehad a rather disappointing first season, given expectations, while on the other end of the spectrum, Myron Pryorwas a pleasant surprise.

Like their counterparts on offense, the men in the trenches on defense have been a consistent strength of Patriots teams under head coach Bill Belichick. But like the o-line, there could be some notable changes to the composition of this position during the offseason.

THE DEFENSIVE LINE ROSTER
(Players listed alphabetically, as of January 2010, with individual analysis below)

92 – Ron BraceManaged two starts, but was inactive half the time. Needs to show dramatic improvement from year one to year two.

65 – Adrian Grady
Another rookie, Grady served exclusively as a practice squad body and is a virtual unknown.

97 – Jarvis GreenMade some comments from which he had to walk back during training camp, to the effect that this was his final season in New England and that he might want to join his hometown Saints. Green wound up starting 12 of 13 games, primarily at Seymour's old spot at right defensive end. He'll be a free agent, however, and will likely test the waters.

91 – Myron Pryor
Beat the odds and made the 53-man roster as a late-round draft pick and appeared in 13 games. Appears to have a promising future with the Patriots.

90 – Darryl Richard
Like Grady, a rookie who toiled diligently on the practice all year.

94 – Ty Warren
Once again, Warren was a fixture at left end, starting 12 of 13 games. But numbers-wise, he had a sub-par year, by his standards. His 57 total tackles were the fewest since his rookie year in 2003. Warren is locked up through 2013, however, and will almost certainly have an opportunity to bounce back.

75 – Vince Wilfork
The biggest question mark on the roster this offseason. Wilfork played the good soldier in '09, deciding to not to sit out to force negotiations, but as the season wore on, his patience appeared to wear thin. He may want to look elsewhere for employment, but the Patriots will probably franchise-tag him, so he'll likely end up back in Foxborough in '10.

99 – Mike Wright
A quality backup who can start in a pinch, Wright is also versatile enough to play every position on the d-line. He also registered five sacks in '09, surpassing his total of four in his previous four seasons combined. Wright is under contract through 2012.

*Up next in the Position Snapshot series: running back, coming Monday, Jan. 25.
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