SAM FARMER / ON THE NFL

Detroit Lions' Matthew Stafford takes great leap forward

The Raiders held on to win, 21-18, blunting Pittsburgh's two-game winning streak and beating the Steelers for the fourth time in five games.

Chief among them

Kansas City is half-perfect, 8-0 for the second time in franchise history, but the Chiefs are going to have to play better than they did Sunday to keep that record unblemished.

After building a two-touchdown lead in the second quarter, the Chiefs failed to put away the Browns after halftime and had to hold on for a 23-17 victory. The NFL sack leaders didn't collect their first sack until the fourth quarter, and Chiefs quarterback Alex Smith was sacked six times.

Still, Kansas City is the league's only undefeated team, and the only one that has yet to allow 20 or more points this season.

Smith, for one, doesn't mind the Chiefs having a target on their back.

"We love it," he said. "You want teams' best shots. You want the stages to get bigger."

None of the eight teams the Chiefs have beaten currently has a winning record. The second half of their schedule features two-game series against Denver and San Diego, and a penultimate game against Indianapolis that could be pivotal in the playoff picture.

The Chiefs, who went 2-14 last season, are the first team in NFL history to start 8-0 after posting the league's worst record the previous season.

In the Super Bowl era, all 20 teams that have started 8-0 have gone on to reach the playoffs, with 12 of those teams advancing to the Super Bowl. Eight of them won it all.

Hamstrung

At the beginning of the season, people were buzzing about Philadelphia's offense and how Coach Chip Kelly might revolutionize the game.

Well, that offense hasn't scored a touchdown in two games. The only time the Eagles reached the end zone in Sunday's 15-7 loss to the New York Giants was when they scored on a fumble return in the fourth quarter. Philadelphia has lost a franchise-record 10 in a row at home.

Rookie quarterback Matt Barkley replaced Michael Vick early in Sunday's game, after Vick was sidelined with a bum hamstring.

In his first game against the Giants this season, Vick suffered a pulled hamstring and missed the next two games. During practice last week, he insisted he was ready to go. There's financial incentive for him to be on the field.

According to contract details first reported by ProFootballTalk.com, Vick gets a bonus of $1.5 million if he plays 90% of the Eagles' offensive snaps — a number that's virtually unreachable now — but is also eligible for bonuses based on lower percentages.

Regardless, it sounds as if he could be out awhile this time.

"I've never had a hamstring injury this bad," he said after Sunday's game.

Barkley, the former USC standout, completed 17 of 26 for 158 yards with an interception.

"I thought I played all right," Barkley said. "I thought I made some good throws and some poor decisions. It's the little things that you just have to hunker down on."

He will get a chance to do that — and probably his first start — when the Eagles play at Oakland on Sunday.

Far from home

San Francisco players weren't happy about the mushy condition of their practice fields in London, but firm footing wasn't a problem for them at Wembley Stadium on Sunday.

The 49ers destroyed Jacksonville, 42-10, and during their current five-game winning streak have outscored opponents, 174-61.

As for NFL fans in London, who paid top dollar to watch the winless Jaguars lose again, there's good news and bad news.

Good news: You might have a team of your own in the coming years.

Bad news: That team could be the Jaguars.

sam.farmer@latimes.com

Twitter: @LATimesfarmer

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