The San Diego Chargers and Denver Broncos kick off Week 8 on Thursday night, and already there are purported contenders in must-win mode, setting the stage for the National Football League’s Separation Sunday atmosphere.

The Chargers are not one of those teams, but Sunday’s loss to the Chiefs raises the stakes of the Thursday game at Mile High.

San Diego (5-2) can pull into a first-place tie in the AFC West by beating the Broncos, who won for the third consecutive week Sunday night as Peyton Manning became the NFL’s all-time leader in touchdown passes.

The litmus test for the Chargers, who have wins over Oakland (0-6), the Jets (1-6), Jaguars (1-6), Bills (4-3) and Seahawks (3-3), is not mission: impossible. Quarterback Philip Rivers led a 27-20 upset last season at Denver and won there in 2011 (29-24).

Good company surrounds San Diego in the standings crunch this week as midseason arrives and could bring the offseason to a few touted contenders before the scheduled change of seasons in the NFL.

Atlanta (2-5) is somehow only one win behind first-place Carolina in the AFC South and the Falcons are 2-0 in the division with a morning tea kickoff time in London on Sunday.

Chicago stands at 3-4 with dissension in the ranks. The woebegone locker room nearly imploded Sunday with pointer fingers flying and accountability lacking. Considering their 0-3 record at home, the Bears could be staring at hibernation with games at New England (5-2) and Green Bay (5-2) on deck and Detroit also 5-2 and dining on Falcons at Wembley Stadium Sunday.

Too soon to be Sleepless in Seattle? Not so in a division overflowing with playoff-quality teams.

After being shocked at St. Louis Sunday, 28-26, the Seahawks (3-3) are third in the NFC West. They already endured a loss at home and the enviable chemistry that made Seattle a Super Bowl champion isn’t there — yet. Dealing volatile wide receiver Percy Harvin to the New York Jets last Friday might harmonize the roster, but the longest road trip of the season — at Charlotte to play the Carolina Panthers — feeds into a second-half schedule pocked with landmines. Two dates with division-leading Arizona (5-1) presents ample chances to regain traction, but considering the Cardinals’ rollaway bags have already packed away a win at CenturyLink Field (2013) under Bruce Arians.

And of course, two games in 17 days against the San Francisco 49ers — Thanksgiving Night at Levi’s Stadium and Week 15 two weeks later in Seattle, Dec. 14 — with a challenging trip to Philadelphia (5-1) in between could spoil Seattle’s holidays.

The good news at the moment for the Chargers is San Diego’s challengers for a potential wild-card spot might be few. Cincinnati (3-2-1), Kansas City (3-3), Buffalo (4-3) and Miami (3-3) are too inconsistent to label contenders at midseason.

Week 7: What we Learned:

Broncos 42, 49ers 17

The Broncos will go as far as Peyton Manning carries them. He was on the money from the outset Sunday night as the Broncos built a 21-10 half time lead behind his first of three touchdown throws, including the record-setting 509th to wide receiver Demaryius Thomas with 3:09 left in the second quarter, which was not only a comment on Manning’s potency, but perhaps says something about that injured and rebuilt 49ers defense.

“He played at the highest level, real excellence,” 49ers coach Jim Harbaugh said. “In all phases, the Broncos were on their game, especially Peyton. Congratulations to him on breaking the record.”

The surprise Sunday, other than the score: Denver running back Ronnie Hillman showing he might be featured back material with a second consecutive strong showing, including a 37-yard run that was the longest allowed by the 49ers since 2010.

Cardinals 24, Raiders 13

Despite improving to 5-1 and remaining atop the NFC West, the Cardinals won’t get overconfident.

“I think we have a group of guys that find ways to win,” Arizona coach Bruce Arians said. “We’re not special, but we have a bunch of guys that are going to play hard for 60 minutes. We know we’re not special. The one thing we talked about all week was you never underestimate an opponent. You darn sure don’t overestimate yourself. We haven’t done anything yet except get to 5-1. There’s a lot of football left with a big game coming home against Philadelphia this week.”

Running back Andre Ellington rose to Arians’ challenge to run the ball even when opponents see it coming. He had 160 total yards Sunday. Ellington carried 24 times for 88 yards and caught six passes for 72 yards. He took a hit to his ribs in the first half, but X-rays at halftime were negative.

Chiefs 23, Chargers 20

The Chiefs stole a page from the Chargers’ playbook and played keep-away. By hogging the ball for 39 minutes, Kansas City kept San Diego’s best weapon, quarterback Philip Rivers, on the sideline. The Chiefs have some decent weapons outside, especially wide receiver Dwayne Bowe, but they leaned on their primary option, which is running the ball. Kansas City’s 154 rushing yards were the most allowed by the Chargers this season.

“We didn’t have 11 guys making plays,” Chargers coach Mike McCoy said. “We didn’t stop them.”

Injuries could be the downfall of San Diego. The Chargers are fond of saying “next man up,” but the bruises are catching up with them. With linebacker Manti Te’o out again and others nicked up, San Diego’s run defense was pushed around with regularity and now on a short week, the blueprint will be out on how to beat the team.

“We’re a no-excuses bunch,” safety Eric Weddle said. “We man up to our mistakes, and we just didn’t get it done today.”

Cowboys 31, Giants 21

While in past seasons the Cowboys did not find the accelerator in the fourth quarter of a tight game, there was an ease about the operation and an apparent team-wide confidence in Dallas that they will get the job done collectively. A few possible clues into why it’s all working:

–Third down is no reason to worry. Dallas came into the game as the NFL leader in third-down efficiency, and converted 9-14 against the Giants.

–The running game continues to excel. The NFL’s leading rushing team pounded out 156 yards, including 128 from rushing leader DeMarco Murray. Dallas able to control the clock once again, holding the ball for nearly 34 minutes.

–In Murray and a dominant front five, the identity of the team has taken hold. Murray set the NFL record for consecutive 100-yard rushing games to open a season with seven. Murray held the previous record of six games with Hall of Fame legend Jim Brown.

Jaguars 24, Browns 6

Center Alex Mack’s absence was glaring, and the Browns’ offense could be in trouble.

Running backs Ben Tate (4.6 yards per attempt), Isaiah Crowell (5.4) and Terrance West (4.4) all came into Jacksonville game with recent success. But all three Browns’ running backs had a tough afternoon. Crowell had the best average per gain at 2.6, followed by Tate at 2.3 and West at 1.6. Half of Tate’s 36 yards in 16 carries came on one 18-yard run. Otherwise he gained 18 yards in 15 attempts.

Quarterback Brian Hoyer, who was averaging 236 yards per game with a passer rating of 99.5, was held to 215 yards — 65 of which came on one completion to Andrew Hawkins — and a passer rating of just 46.3. Only two drives reached the red zone, and both resulted in field goals.

“We’ve got to take this loss for what it is, that we got our butts handed to us,” Hoyer said. “But it’s a long season, we’ve got a chance to move on and get a couple wins at home the next two weeks.”

Bills 17, Vikings 16

Quarterback Kyle Orton might have notched his second fourth-quarter comeback in three starts, but it will be tough sledding for the Bills without running backs Fred Jackson (groin) and C.J. Spiller (collarbone). Jackson will miss 2-4 weeks, and Spiller is out for the season.

The Bills (4-3) won despite turning the ball over four times and allowing six sacks, just the second time in history they have accomplished that feat.

“It doesn’t matter how you win it,” Orton said. “You never apologize for winning a game in this league. It’s too hard.”

Orton was 31-of-43 passing for 283 yards and two touchdowns. He threw one interception and lost a fumble.

There is good news going forward: wide receiver Sammy Watkins caught nine passes for 122 yards and both touchdowns for the Bills.

Packers 38, Panthers 17

Quarterback Aaron Rodgers is on a roll, to the extent that coach Mike McCarthy said he’s playing far better than 2011, when Rodgers was NFL MVP.

The only quarterback in NFL history to have 15-plus touchdowns and zero or one interception in his first six games of a season, Rodgers threw for three touchdowns and wasn’t picked off against the Panthers. He was in total command, whether it was his accurate throws, drawing the Panthers offside twice or catching them with 12 men on the field.

“There’s going to be interceptions from time to time, it’s just limiting the number of 50-50 balls that either they get their hands on or get tipped or are poor throws,” Rodgers said. “If they’re not touching the ball that much or at all in a game, that means you’re being as accurate as you want to be.”

Even better for the Packers, they contained quarterback Cam Newton and slowed a spread-option attack to a halt. The Packers had one takeaway but dominated a Carolina attack that scored 37 points against Cincinnati’s formidable defense last week. Carolina’s first five possessions ended in punts, and the Panthers managed only 113 total yards in the first half.

“Defensively, we needed to stop Cam Newton,” McCarthy said. “He was our focus all week. We have a lot of respect for what he does and what he does in that scheme. We were able to get that done.”

Lions 24, Saints 23

The Saints lost again on the road, and the Lions look like they are coming of age under first-year coach Jim Caldwell. Detroit survived two more Matt Stafford interceptions and erased a 13-point deficit in the final 3:38.

“We’re finding ways to win,” said Lions quarterback Matthew Stafford, who threw the touchdown passes. “We came in here and played Buffalo (the last home game) and didn’t find a way to win that game. Today, we did the opposite. We found a way to win it and that’s what we’ve got to have more of.”

Colts 27, Bengals 0

The Colts limited Cincinnati to 135 total yards and one third-down conversion in a thorough thumping that kept both teams heading on their present courses. Indianapolis (5-2) won its fifth in a row while the Bengals (3-2-1) extended their winless streak extend to three.

“They’re hard to come by, when you can have a defensive performance like that,” said Colts head coach Chuck Pagano. “We’re starting to get a glimpse of what we envisioned when we got together a couple years ago, what we wanted to build and it looks like that monster is starting to rear its head a little bit.”

Quarterback Andrew Luck completed 27 of 42 passes for 344 yards and two touchdowns, his fifth consecutive game of at least 300 yards.

Redskins 19, Titans 17

Neither team looked special Sunday, when Colt McCoy came off the bench and the third-string quarterback, in his first game action since 2012, to push the Redskins to a 2-5 overall record. The Titans, playing again without Jake Locker, dropped to 2-5.

It could be any week now — as early as next Monday at Dallas — when Robert Griffin III returns under center for Washington. But the Redskins’ running game, one of the NFL’s best the past two seasons, continues to struggle even though Pro Bowl back Alfred Morris, fullback Darrel Young and all but one of last year’s starting linemen are back. Morris gained just 54 yards on 18 carries after producing just 70 yards on 26 carries the previous two games.

Rams 28, Seahawks 26

Russell Wilson did everything in his power to push the Seahawks past the Rams, but St. Louis legged out the upset and might have found the answer to a punchless ground game.

Running back Tre Mason could prove to be third-round gold. The rookie from Auburn ran with a burst, picking up a team-high 85 yards on 18 carries and his first NFL touchdown. There was also more promising play from quarterback Austin Davis, who was 18 of 21 in a relatively low-risk game plan.

But the difference in the game was a memorable side show by the Rams special teams. The Rams pulled a trick, misdirection punt return for a 90 yard touchdown and, more gutsy, punter and former high school quarterback Johnny Hekker completed a game-clinching, 18-yard pass to Benjamin Cunningham on fourth-and-3 from his own 18 with 2:55 left and Seattle anxious to get the ball and pull out a win.

Ravens 29, Falcons 7

Baltimore belongs in the conversation with the other AFC elite. The Ravens lead the NFL in point differential and are clicking in all phases of the game.

It’s not just the defense that is failing the Falcons. Atlanta was shut out for three quarters and another injury on the offensive line — center Peter Konz left the game — could mean quarterback Matt Ryan is a sitting duck against the Lions’ polished pass rush Sunday in London.

“We have nine games left and I know every man in that locker room and every coach in that room will work their (butts) off this week to get prepared for the Detroit Lions. I have no doubt what the makeup of these football players and coaches and the organization we have in Atlanta,” coach Mike Smith said.

Dolphins 27, Bears 14

Miami’s offensive line is vastly underrated since the return of Mike Pouncey, and the Dolphins are close to achieving the type of balance coach Joe Philbin knows will be required to make it to the postseason.

With a 4.2 per-carry average, the Dolphins made life easier for quarterback Ryan Tannehill, who turned in one of his best all-around efforts, including six carries for 48 yards. He completed his first 14 passes and the Dolphins’ defense never let the Bears get going.

That led to acrimony in the locker room where wide receiver Brandon Marshall lashed out at his quarterback and remained steamed minutes later when media entered, calling the Bears’ 3-4 record “unacceptable.”

— Some content was contributed by Sports Xchange correspondents who covered each game.