The Belichick-era Patriots have never been known as a rushing team. If anything, the conventional wisdom has been that they’ve used short passes as their de facto running game, and run the ball only as a change of pace or to kill the clock toward the end of games.

Throw that so-called wisdom out the window. Despite the lack of a signature rusher, or even a clear starting running back, the Patriots are on pace for their best rushing season of the Belichick era — in fact, their best since the 1980s.

Thanks to the unheralded rotation of Sammy Morris, Kevin Faulk, LaMont Jordan, and BenJarvus Green-Ellis, the Patriots are on pace for 2,202 yards rushing. The 1,927 yards they have gained so far is more than last season, and they are well on their way to surpassing the 2,134 yards the team put up in 2003, when Corey Dillon led the way with 1,635 yards.

Even more impressive is the team’s 4.5 yards per carry average, by far the highest of the Belichick era. In fact, it is the highest since 1983, when Tony Collins led a rushing attack that piled up 2,605 yards and averaged 4.8 yards per carry.

There are many possible reasons: Tom Brady’s season-ending knee injury has forced the Patriots to rely more on the run; the offensive line is excellent and keeps getting better; the running backs are better than observers realize; the competition has been weak at times.

“Good blocking and good running,” is all it comes down to, Belichick said.

“The backs have done a good job — they’ve all done a good job. We’ve had some good blocking by the offensive line, some good play calling, and some good adjustments at the line of scrimmage at times,” he said.

Belichick said that Matt Cassel has smartly audibled the Patriots out of the run and into passing plays when he sees that a run might fail. And he said that few have recognized how important the blocking of receivers Randy Moss and Wes Welker has been to establishing the ground game.

“I think that one of the real underrated aspects of the running game has been the blocking of our receivers, And (Sunday), Randy and Wes in particular, those guys did a great job of downfield blocking,” Belichick said.

The Patriots’ running game was on full display Sunday against the Raiders, as New England hammered out 277 rushing yards.

Morris rushed for 117 yards. Jordan for 97. Faulk chipped in with 45. And the mobile Cassel, who has rushed for 232 yards this season, threw in 18.

The Patriots now boast the seventh highest-ranked rushing offense in the league, averaging 137.6 yards per game — and all this with titular starter Laurence Maroney spending most of the season on injured reserve with a shoulder injury.

Morris is the team’s leading rusher, but he’s nowhere near the oft-cited 1,000 yard mark that measures the greatness of a running back. The multi-headed attack is fine with him, as long as the team keeps winning.

“I’d much rather have 600 yards rushing, 700 yards rushing on the season, and win, than me have 1,500 and be 4 and 12,” he said.

Morris credited the Patriots play calling and the team’s complex offensive game plan with opening up running lanes.

“I think it’s a lot of factors … obviously, you factor in the offensive schemes, and then you’ve got to factor in the passing threats we have,” Morris said.

“I’m always quick to give the offensive line credit. They’re big guys, and they’re pretty agile, and they’re able to get on their blocks and sustain them, and they’re able to get us into the second level of defenders. And I always say it’s up to the back after that,” he said.

The Patriots, Jets and Dolphins are all 9-5, and all are vying for the AFC East lead. With the Patriots likely needing to win out to make the playoffs, New England’s runners know they must have big games against the remaining opponents, Arizona and Buffalo.

The Cardinals are ranked 14th against the run, allowing 107 yards per game, while the Bills allow 114, 19th in the NFL.

dbarbari@projo.com