NFL is full of quick-change artists

The New Orleans Saints are toast. The Arizona Cardinals have turned the corner. It’s time for Norv Turner, Rex Ryan and Andy Reid to go.

Some of those bold statements might hold up this NFL season, but some will sound absurd in a few months.

It happens every year. People make dramatic judgments on what has happened in the first half of the season, only to watch those predictions crumble in the second half.

In the case of the Cardinals, that’s already happening. The team that won its first four games has now lost three in a row, with San Francisco coming to town Sunday, followed by road games at Green Bay and Atlanta.

It was only a few weeks ago when many observers were calling the Cardinals one of the best teams in football. By mid-November, Arizona could be 4-6.

Are the Saints done? They might be, especially considering the way Atlanta is running away with the NFC South. But in recent years, a lot of teams have flipped a switch and come alive in the second half of the season, the way the New York Giants did last year.

The Giants, remember, were 7-7 in mid-December and needed to win their final two games to secure a playoff spot, one they ultimately parlayed into a Super Bowl title.

A year earlier, the Packers needed to win their regular-season finale to grab the last wild-card spot and sneak into the postseason, where they promptly ran the table on their way to another Lombardi Trophy.

In a 16-game season, every victory is important. That said, teams that win in September and October are frequently the ones that fade down the stretch. Washington, for instance, won three of its first four games last year … then won only two more games all season. Buffalo got to 5-2 … and finished 6-10.

The question is, who are this season’s Giants? Which franchise is going to hit the seam at the right time and make that surprising run for a championship?

If there’s a distinguishing characteristic of this season so far, it’s competitive balance. Three-quarters of the teams have at least three victories, only Atlanta is undefeated, and only three AFC teams have winning records — Houston, Baltimore and New England.

With halftime of the season fast approaching, we can bank only on this: It’s just getting started.

Popularity contest

Forbes.com published lists this week of the top 10 most and least popular players in the NFL, based on a fan survey conducted by Nielsen and E-Poll Market Research.

The most-liked player was Pittsburgh and former USC safety Troy Polamalu, and the least-liked was Detroit defensive tackle Ndamukong Suh.

Worth noting was that seven of the least-liked players were quarterbacks, among them two from USC (Matt Leinart and Mark Sanchez) and two from the Dallas Cowboys (Tony Romo and Kyle Orton).

Washington’s Robert Griffin III, ranked seventh among the most-liked players, was the only rookie to appear on either list. Tim Tebow didn’t appear on either.

Digging up the past

What’s silver, black and dirty all over?

The Oakland Raiders, evidently.

That’s what Kansas City linebacker Tamba Hali says, anyway, claiming in the run-up to Sunday’s game against Oakland that the Raiders are cheap-shot artists.

“It’s tradition,” Hali told reporters this week. “The Raiders, they come in, they cheap-shot, they hit you. I’m not saying names. It is what it is. We’ve got to be ready to play and keep our composure, stay poised and be able to get this win.”

The Raiders, who have a new coach in Dennis Allen and — in the post-Al Davis era — a general manager in Reggie McKenzie, have been working on improving their reputation. So maybe Hali is simply operating on old information.

“Any time you play the game, you should play with a chip on your shoulder,” Oakland defensive lineman Richard Seymour said, according to the Kansas City Star. “You should play with an attitude.

“But in terms of being dirty, going out to hurt guys, I don’t think I play that way or any of my teammates [play that way.] I don’t stand for it.”

sam.farmer@latimes.com

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