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Ron Brace, Myron Pryor, Brandon Deaderick and Kyle Love were released this offseason by the New England Patriots. All played defensive tackle—the position at the heart of the first line of defense.

A purge at one position typically indicates a problem area for a team. But the Patriots run defense finished ninth overall in yards allowed (1,630) and sixth overall in yards per attempt (3.9 average) in 2012.

Upon further analysis, though, good teams don’t fear New England’s run defense and for good reason.

New England’s run defense was aided by the prolific offense that forced many opponents to abandon running the ball just to keep up with the Patriots. In close games, however, opponents pounded the ball for four quarters and wore down New England’s run defense.

The first step in evaluating the run defense was to separate the blowouts from the games decided by 10 points or less. The blowouts were wins over Tennessee, Buffalo, St. Louis, Indianapolis, the New York Jets, Houston and Miami. The close wins were over Denver, the Jets, Buffalo, Miami. and Jacksonville, while the close losses were to Arizona, Baltimore, Seattle and San Francisco.

While yards per carry were nearly even (3.8 yards/attempt in blowouts, 3.9 in close games), the average yards per game jumped from 87.1 to 109.9.

The increase of 22.8 rushing yards per game doesn’t sound like much, but that was gained with an additional 5.1 more attempts per game. That’s a yards-per-carry average of 4.5 yards.

To put that in perspective, 109.9 yards allowed per game would rank 14th in the NFL in 2012. Eight yards more than New England’s season average of 101.9 rushing yards per game would change the Patriots run defense from good to mediocre.

In an attempt to be fair, the 31 yards gained by San Francisco’s Dashon Goldson on a fake punt was subtracted from the total yards, as was his single rush attempt. If these numbers were included, the rushing yards would increase from 989 yards to 1,020 yards, 254 attempts, a 4.0 yards-per-carry average and 113.3 yards per game allowed.

Run Defense in Blowouts Versus Close Games Type of Games Games Attempts Yards Yds/att Yds/gm Blowouts 7 161 610 3.8 87.1 10 Points or Less* 9 253 989 3.9 109.9 2012 Totals 16 415 1,630 3.9 101.9 *Dashon Goldson’s one rush for 31 yards subtracted from totals

Brace and Pryor couldn’t stay on the field. It might be more about a change in approach for the defense.

Only six 300-pound space-eating defensive linemen are currently on the roster. Based on the current roster, the defensive linemen won’t be waiting for the ball-carrier to come to them in 2013. The approach will be less two-gap play and more penetrating, getting into the backfield and making the play kind of D-line play.

Vince Wilfork is the prototype for what the Patriots want at defensive tackle. Free-agent addition Tommy Kelly had 14.5 sacks combined in 2010 and 2011, and New England hopes he can regain his penetrating ways. Armond Armstead had six sacks in his only season playing for Toronto in the CFL.

The remaining DTs are Marcus Forston, a rookie free agent in 2012 who spent most of last season on the practice squad, and 2013 restricted free agents Cory Grissom and Dewayne Cherrington.

That’s a lot of change at one position, but it had to be done. Last year’s run defense wasn’t as good as the numbers suggested.

Questions? Comments? Send to randolphc82@comcast.net.