Detroit Lions’ Matthew Stafford takes great leap forward

As the final seconds wound down in Sunday’s game against Dallas, Detroit quarterback Matthew Stafford frantically urged his teammates to the line of scrimmage. He gestured wildly, giving everyone the impression he planned to spike the football to stop the clock, giving the Lions one last chance from the Cowboys’ one-yard line.

Then he noticed the Cowboys’ sleepwalking linebackers. They weren’t ready to explode off the ball. They were in position, but lethargically waiting for him to stop the clock.

“I told everybody I was spiking it. I was screaming, ‘Clock!’ I was going to spike it,” Stafford said. “It was a feel thing.… I saw linebackers kind of standing there.

“I looked down, and we were [close]. ‘Shoot, I’m going to go get that.’”

So to the surprise of everyone — including his Lions teammates — Stafford took the snap, leaped forward, and jabbed the ball across the goal line for the winning touchdown in a 31-30 victory at Ford Field.

A game that will go down as an offensive masterpiece for Detroit — 623 yards, including 329 yards receiving by Calvin Johnson — was decided by a quick-thinking quarterback who took advantage of a glimpse of an opportunity.

The Cowboys, meanwhile, showed more fight on the sideline than they did on the field. TV cameras twice caught receiver Dez Bryant melting down on the sideline, first screaming at wide receivers coach Derek Dooley, and then engaging in a heated argument with tight end Jason Witten. Linebacker DeMarcus Ware stepped in and separated the two.

Both Coach Jason Garrett and quarterback Tony Romo defended Bryant’s outbursts as more passion than petulance.

“He’s a competitive guy,” Romo said of the star receiver. “He’s never complained to me about getting the ball. He knows that the ball is going to where it’s supposed to. When you guys see emotion sometimes from Dez, it’s just trying to rah-rah, more than it is being a ‘me’ guy. That’s not who Dez is.”

It’s no wonder the Cowboys were boiling with frustration. The lesson of Week 8: Don’t let down your guard.

The Miami Dolphins did. They built a 17-3 lead in New England, only to watch the Patriots — who were booed by their fans at halftime — spring to life with 24 unanswered points in the second half.

It was not a good game for Tom Brady, who said he feels “awesome” although his swollen right hand might indicate otherwise. He threw for 116 yards with a touchdown and an interception.

The Patriots’ defense played a big part in Sunday’s turnaround, ramping up the blitzes in the second half and sacking Miami’s Ryan Tannehill six times.

“We’ve got to keep the same mind-set the whole game,” lamented Dolphins receiver Mike Wallace after the 27-17 defeat. “We just have to step on their throat.”

Washington knows the feeling. The two-win Redskins had a 21-7 lead in the third quarter at Denver, only to watch the Broncos score five touchdowns and a field goal in the final 11/2 quarters on their way to a 45-21 victory.

Through eight games, the Broncos have scored 343 points, an NFL record for the first half of any season.

Talk about ending with a whimper. The Redskins’ last six possessions: a fumble, a three-and-out, a 15-yard punt, and four interceptions.

In that loss, Redskins quarterback Robert Griffin III took a pounding, and didn’t finish the game, although he didn’t appear to be wincing as he walked the sideline.

For Pittsburgh, the most glaring letdown happened on Oakland’s first play from scrimmage. Raiders quarterback Terrelle Pryor faked a handoff, and turned upfield through a massive hole in the Steelers’ defense. Nobody caught him as he ran for a 93-yard touchdown, the longest run in Raiders history, and the longest touchdown run by a quarterback in NFL history.

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