RENTON — Not too long ago, the NFC West was a punch line. Now it’s the division that will punch you in the mouth.

Less than two years after the Seahawks won the “NFC Worst” with a 7-9 record, the division is quickly silencing its critics not just with a physical brand of football more commonly associated with the AFC North, but also with some impressive wins to open the 2012 season. Sure there are plenty of uninformed people who still probably look at the NFC West and assume it’s a division comprised of San Francisco and three bad teams you might as well ignore, but if you’ve actually been paying attention, then you know that the division is a laughing stock no more.

It starts with the 49ers, who were 13-3 last year and were a play or two away from advancing to the Super Bowl. A lot of folks, this writer included, figured San Francisco would take a step back in 2012. The 49ers were unusually healthy last year. They had a turnover ratio (plus-28) that seemed impossible to repeat. And quarterback Alex Smith — well, we’ve all been conditioned to think that he’s just no good, when in fact it may be that the former No. 1 pick is just finally hitting his stride now that he’s in a stable situation for the first time in his career. Perhaps the 49ers will come back to earth a bit this year, but they’ve shown no signs of that yet, winning their opener at Green Bay, then beating Detroit, another team that made the playoffs last year. So while it’s way to early to know for sure, it is possible that we were all wrong about the 49ers coming back to the pack this year.

And this year, it’s looking more and more likely that the 49ers won’t be the only playoff contender in their division. Arizona was largely dismissed coming into the season thanks to uncertainty at quarterback, but the Cardinals are 2-0 and coming off of shocking win in New England. Going back to last season, the Cardinals are 9-2 since starting the year with a 1-6 record. Seattle also finished last season strong, and after a close loss in Arizona, the Seahawks thumped Dallas on Sunday, physically dominating a Cowboys squad that many had pegged as one of the top teams in the NFC after they knocked off the defending Super Bowl champion New York Giants in Week 1. Throw in St. Louis, which after going 2-14 last year opened this season with a close loss at Detroit and a comeback win over Washington, and it is looking more and more like the NFC West is a division of teams ready to push back rather than be pushovers.

“I think it is a very aggressive division,” Seahawks coach Pete Carroll said. “It’s shaping up to be a really cool division, and I think the people are going to look at it a lot differently than they have, let’s just say a couple years ago, when we looked at it the other way, I guess, back then.”

What is particularly interesting about the rise of the NFC West isn’t just that the teams have all taken steps forward over the past couple of years, but the way they’ve done it. In a league in which teams are passing for more yards and scoring more points than ever, teams like the 49ers, Seahawks and Cardinals are building playoff contenders around stingy, hard-hitting defenses. The Rams’ defense hasn’t been impressive so far this year, but head coach Jeff Fisher has a defensive background, and has plenty of young pieces in place to build a winner around a strong defense. And yes, you can point out the number of offensive-minded teams that have won titles in recent years, but if just two plays had gone differently in last year’s conference championship games, the Super Bowl could have been a Baltimore-San Francisco matchup.

Years ago, the 49ers helped revolutionize the game by winning multiple titles with Bill Walsh’s West Coast offense. Now teams like San Francisco and Seattle are going old school, trying to win with good old-fashioned, smash-mouth football. There is nothing revolutionary about this formula, yet it seems almost experimental in a league that has become so pass-happy. Just don’t expect coaches like Carroll and the 49ers’ Jim Harbaugh to change just because everyone else seems to think you need an explosive passing attack to win games. Just about every coach at every level of football will tell you that they want to run the ball and play good defense, but very few will commit to it like Carroll and Harbaugh have.

“There’s nothing that replaces playing (special) teams, great defense and running the football,” Carroll said. “That’s pretty hard. You’ve got to throw a lot of balls to overcome that, take a lot of chances to do that. We certainly want to throw the football, and we’ll throw it more as we go — we’ll be able to throw more as we grow with this team — but that’s not to make anybody happy. We’re doing it the way we want to do it right now. We’ll see how it goes.”

This week, the NFC West will continue its push for respect and national relevance. The 49ers will be expected to win in Minnesota, but if the Rams could win in Chicago, or if the Cardinals could beat the 2-0 Eagles, or especially if, in front of a Monday Night Football audience, the Seahawks beat the Packers, it will be even harder to ignore the division that two years ago was considered one of the worst in NFL history.

“I can’t tell you how much (the division has improved), but it has,” Carroll said. “We’ve improved. The ‘Niners played so well last year and did such a good job throughout the season, and they look like they’re really legit again. The rest of us are trying to catch up a little bit. They had 13 wins last year, that’s a lot of wins. It’s happening, though. However, it’s happening. … It seems to be growing out here in the West. I don’t know what it is, but everybody’s getting better with their football. It’s pretty cool.”

Herald Writer John Boyle: jboyle@heraldnet.com.