Trick? Or treat?

It’s the NFL version of the irresistible force vs. the immobile object on Sunday, when the Raiders’ Darren McFadden and Michael Bush run into the Seahawks’ No. 2-ranked run defense at a place where it’s always Halloween.

Just the mention of a Halloween game against the Raiders at Oakland Coliseum makes Colin Cole smile, and then laugh.

“Obviously Oakland is going to be a raucous place,” said Cole, the Seahawks’ nose tackle and anchor of the No. 2-ranked run defense in the NFL. “You know, Halloween day, the fans might be just that much more, uh, …”

As Cole paused to find just the right word, someone interjected, “Festive.”

“There you go,” Cole said.

If only the Seahawks’ primary concern for Sunday’s game against the Raiders was limited to those “festive” fans who show up in Halloween-type costumes for every game.

But there’s also the Raiders’ running game, which cranked out 328 yards in last week’s 59-14 romp over the Broncos in Denver. That’s 3-2-8, as in the kind of rushing yards a major-college university slaps on a lower-division opponent during the cupcake portion of its schedule.

“Obviously with the success they had last week they’re going to try to establish that early and they’re going to try to set that up as their go-to thing,” Cole said. “Obviously they’re going to try and test us and see if we’re going to continue to do what we’ve been doing.”

What the Seahawks have been doing is shutting every running attack they’ve faced. They are allowing averages of 77.5 rushing yards per game and 3.3 yards per carry – each mark ranks second in the league to the Pittsburgh Steelers (63.7 and 2.8).

And the Seahawks’ averages are actually inflated after they yielded 113 rushing yards and a 5.7-yard average to the Arizona Cardinals’ Tim Hightower and Beanie Wells last week – both season highs.

The Raiders will come at the Seahawks with a similar 1-2 punch: Darren McFadden, who had a career-high 165 yards against the Broncos, not to mention four touchdowns; and Michael Bush, who had 52 yards a TD.

Bush is a basher, a 245-pounder who makes his living running between the tackles – and running over would-be tacklers. McFadden also has size (6-2, 210), but it’s his speed (4.33 seconds for 40 yards at the scouting combine in 2008) that makes him special.

“He has serious breakaway speed,” Cole said. “Everybody we’ve faced has their own talents. But McFadden is unique in that he’s a huge guy and he’s got the speed of some of the elite backs out there.”

It’s not just that the Raiders have two backs; it’s how they use them.

“Bush, he’s a bruiser. He wants to get downhill on you,” Cole said. “McFadden, he’s a bounce-out guy who wants to get to the edge so he can get into space.”

The Seahawks have faced both kinds of backs already. They limited the 49ers’ Frank Gore to 38 yards on 17 carries, and he is averaging 81.9 for the season. They limited the Rams’ Steven Jackson to 70 yards on 22 carries, and he’s averaging 88.1 yards. They limited the Bears’ Matt Forte to 11 yards on eight carries, and he was coming off a 166-yard performance the week before. The Cardinals’ Hightower “got” them last week, rushing for 59 yards on six carries.

This is yet another challenge, but a somewhat different challenge, because of the backs the Seahawks are facing and where they will be facing them.

“With his bust and his ability to make people miss, he’s the real deal,” defensive coordinator Gus Bradley said of McFadden. “He just looks like he’s playing with a lot of confidence.”

So what might start with Cole will need to include as many defenders as the Seahawks can bring – and as quickly as possible.

“Wrap up. Get guys to him. The old swarm-tackle deal,” Bradley said. “Because he can make the first guy miss. The thing we’re trying to simulate (in practice) is just the speed. He gets into a lane and then you have to take the right angles on him.

“We saw last week there were some bad angles, and that’s just because of the burst he has.”

And just when you’re starting to become less blinded by McFadden’s speed, Bush comes in with his rock-’em, sock-’em style.

“They mix it up pretty well,” Cole said.

Fear the challenge? Hardly. Embrace the challenge? Well, Cole also answered that one, and this time with a straight face.

“Obviously it’s going to be a huge week for them,” he said, “going against the No. 2-ranked rush defense.”