Change you can believe in? It’s business as usual in the NFL

The 49ers couldn’t lose. The Browns couldn’t win. The Vikings were the sleepers. The Jets were the snorers.

In the ever-changing NFL, though, that was . . . so last week.

Everything was turned on its head Sunday — or knocked on its backside, as was San Francisco quarterback Alex Smith. He was sacked five times in a shocking 26-3 loss at home to the New York Giants.

PHOTOS: The Week in Sports

Cleveland, which entered the weekend as the only winless team, halted an 11-game losing streak with a 34-24 win over Cincinnati, the Browns’ first victory over an AFC North opponent in nine tries.

“It was fun to see guys jumping around and happy,” said Cleveland kicker Phil Dawson, noting several of his teammates were new to the sensation of winning an NFL game. “They never had that feeling before and it was great to see.”

Minnesota, the surprise team of the season so far, was undone by Washington rookie Robert Griffin III, who returned from a concussion suffered the previous Sunday to throw for a touchdown and run for two more in a 38-26 Redskins win.

And the New York Jets, seemingly locked in a downward spiral, pulled together their most impressive performance with a 35-9 win over Indianapolis that included no turnovers for the first time in 17 games, a leaping body bump between Mark Sanchez and Tim Tebow, and some pinball wizardry by running back Shonn Greene: 161 yards, three touchdowns.

“We want to be a team no one wants to play,” Jets Coach Rex Ryan said. “And we’re on our way.”

Heading into the weekend, the 49ers were that team. They had outscored their previous two opponents, 79-3, and looked poised to avenge their loss to the Giants in the NFC championship game — or at least turn the page on that memory.

Through the first five games, Smith had the league’s best passer rating, and eight touchdowns to only one interception. He was picked off three times by the Giants, and the 49ers couldn’t establish their usual steadfast run attack.

The other Bay Area team gave a surprisingly competitive performance. The Raiders threw a scare into the undefeated Falcons, intercepting three Matt Ryan passes in the first half at Atlanta — Oakland’s first three interceptions of the season — but ultimately losing, 23-20, on Matt Bryant’s 55-yard field goal.

Raiders quarterback Carson Palmer said the turning point in the loss was an interception late in the fourth quarter that Atlanta’s Asante Samuel returned 79 yards for a touchdown, even though Oakland came back to forge a tie.

“We fought hard all game,” Palmer said. “We had a great game plan, and I let the team down. I let our fans down. Making the mistake I made was crucial, and that’s on me. That’s my fault.”

Then again, there’s always next week. And in the unpredictable NFL, sometimes that’s all it takes.

Head games

The Redskins reportedly will incur a “hefty fine” for not immediately disclosing that Griffin had suffered a concussion during their previous game against Atlanta, according to a Fox Sports report. During the game, the Redskins had announced that Griffin was “shaken up” but provided no update. After the game, Redskins Coach Mike Shanahan said Griffin had sustained a “mild concussion.”

The quarterback participated in limited practice Wednesday and Thursday but worked out in full Friday and started Sunday against the Vikings.

Doing the legwork

In a league that’s so competitively balanced, games often come down to field goals. That was certainly the case in Week 6, with seven of the first 12 games decided by three points or fewer.

Following a game-winning kick Thursday by Tennessee’s Rob Bironas, Atlanta’s Bryant, Detroit’s Jason Hanson and Buffalo’s Rian Lindell kicked game-winners Sunday.

On the flip side were Dallas’ Dan Bailey, who was wide on a 51-yard kick that would have beaten Baltimore; St. Louis rookie Greg Zuerlein — nicknamed “Legatron” — who missed three, including a 66-yarder at the end that had the distance but not the direction; and Arizona’s Jay Feely, whose team lost in overtime after he made a club-record 61-yarder in the fourth quarter but followed that by clanking a 38-yarder off an upright in overtime.

Through five games, the NFL was on a record pace in terms of kicking accuracy. Kickers had made 88.6% of their field-goal attempts (272 of 307); the season record is 84.5% (845 of 1,000).

Tricky Tebow

So far, Tebow’s biggest contribution to the Jets has come on special teams. He has converted three first downs out of punt formations, the latest coming Sunday when he took the snap on a fake and threw a dink pass to Nick Bellore, who ran down the seam for 23 yards.

A Chief concern

Kansas City has a dubious distinction through six games. The Chiefs are the only team that has yet to have a lead at any point in regulation. Their lone victory came in overtime at New Orleans. The Chiefs have been outscored, 51-6, in the first quarter.

Making a stand

After two brutal outings, Buffalo’s defense came through in a 19-16 overtime victory at Arizona, ending the Cardinals’ eight-game home winning streak.

The Bills sacked Kevin Kolb five times and limited Arizona to 150 yards passing. Kolb left with roughly two minutes left in regulation after suffering a rib and chest injury and was replaced by John Skelton.

Buffalo’s Jairus Byrd had two interceptions, the second setting up the game-winning field goal.

Bad news for Baltimore

Two key Ravens defenders sustained season-jeopardizing injuries. NFL.com reported that the team fears All-Pro linebacker Ray Lewis’ arm injury is a torn triceps, which would probably end his season. And cornerback Lardarius Webb had to be helped off the field after banging his knee.

After the game, Ravens Coach John Harbaugh painted a grim picture of Webb’s situation, one that likewise would be season-ending.

“Lardarius Webb does not look good right now,” he said. “It’s a potential ACL. We’ve got a problem there. We don’t know for sure, but that’s what it looks like right now.”

Seattle reign

In a matchup between the NFL’s No. 1 offense (New England) and No. 1 defense (Seattle), it was the Seahawks who came out on top, edging the Patriots in Seattle, 24-23.

It was Pete Carroll’s first victory over New England, the franchise he coached for three seasons in the 1990s.

“That was a long time ago and there have been a lot of games,” Carroll said. “I really love [Patriots owner] Robert Kraft; he’s a great man and he’s been great throughout the years about our separation of sorts. I respect the heck out of him. But I’m a competitor and, heck yeah, I want to win against those guys.”

The signature play was a 46-yard touchdown pass from Seattle rookie Russell Wilson to Sidney Rice with 1:20 remaining.

“If guys didn’t believe in him,” Seahawks safety Earl Thomas said of Wilson, “I guarantee they believe in him now.”

sam.farmer@latimes.com

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