Then came the Royal treatment of Oakland, and the gift from Mr. Ed (Hochuli).

Suddenly, the Broncos looked like a racehorse primed to go wire-to-wire, blinders effectively blocking out injury after injury and a gunslinging quarterback rewriting the record books.

Then, just when it appeared the West was won, that seemingly insurmountable lead against San Diego has all but slipped away.

An ice-cold Chargers offense got hot in frigid Kansas City, then rained on Tampa Bay's parade.

Conversely, the Broncos defense sprung a few more leaks, the red-zone offense stalled and the mood, like the temperature, turned from balmy to blue.

Now, in two days, the same field that witnessed the Broncos' greatest win (Super Bowl XXXII) could serve as the scene for its greatest collapse. Win or tie and the Broncos are in the playoffs; lose, and they'll stay home after leading the division by three games with three games to play.

"This is a playoff game for us," tight end Daniel Graham said. "Our backs are against the wall."

While Broncos fans wait for that season-ending showdown Sunday night (6:15, KUSA-Ch. 9) and hope for a happy ending, here's how delight turned to desperation.

Seeing red and black

The Chargers are one game behind the Broncos, but they did something Denver could not - sweep the lowly Raiders and Chiefs.

In Week 4, Kansas City steamrolled the Broncos with 213 rushing yards, 198 from Larry Johnson. It didn't help the Broncos committed four turnovers in a 33-19 loss.

San Diego hardly looked like a worldbeater against the Chiefs, escaping with two one-point wins.

In the first on Nov. 9, Chargers safety Clinton Hart knocked down a two-point conversion pass from Tyler Thigpen with 23 seconds left to preserve a 20-19 win.

In the second on Dec. 14, the Chargers rallied from an 11-point deficit in the final 1:19 to eke out a 22-21 victory.

It was made possible with an onside kick that Kassim Osgood clutched at the bottom of the pile.

"There was punching, grabbing, scratching," Osgood told The San Diego Union-Tribune. "I got bite wounds. . . It was crazy."

Four plays later, quarterback Philip Rivers passed 10 yards to Vincent Jackson for the go-ahead score, then the Chiefs' Connor Barth missed a 50-yard field-goal attempt on the last play of the game.

Like that, the Chargers were alive.

Highs, lows

The story wasn't quite so dramatic against the Raiders as San Diego won 28-18 and 34-7.

But for the Broncos, the Oakland series summed up their roller-coaster season.

In the Monday night opener, they racked up 441 yards and turned rookie Eddie Royal (nine catches, 146 yards, one touchdown) into a prime- time player.

But in the Nov. 23 rematch at Invesco Field at Mile High, the Broncos let a former player haunt them. Ashley Lelie caught four passes for 92 yards and a touchdown in a 31-10 romp.

The run defense was exposed, again, as Justin Fargas averaged 4.5 yards a carry and the secondary was spotty as erratic quarterback JaMarcus Russell completed 10-of-11 passes.

"It's just been a roller coaster, up and down with the injuries and the inconsistencies. You just didn't know which team's going to show up," Graham said.

What's his name?

Or which back would end up carrying the ball.

While LaDainian Tomlinson hardly has had one of his best seasons (1,014 rushing yards, 426 receiving), he has been in the Chargers starting lineup since Week 1, albeit bothered by turf toe.

The Broncos have gone through seven backs (Anthony Alridge, Selvin Young, Andre Hall, Michael Pittman, Ryan Torain, Peyton Hillis and P.J. Pope), and it appears the one who was selling cell phones in Aurora a few months ago (Tatum Bell) will be asked to carry the load in San Diego.

A team that had 1,000-yard rushers in five of the past six seasons has had only one 100-yard rusher this year - Hillis against the Jets.

Law and disorder

Yet were it not for Hochuli, the Chargers already would have locked up the AFC West title.

The Phoenix lawyer with the buff physique and a cult following suddenly became the most hated man in San Diego when he whistled Jay Cutler's last-minute fumble an incomplete pass in the Week 2 meeting.

The Broncos got another shot, scored a touchdown, then converted a two-point conversion for the 39-38 win.

Hochuli received hate mail and even death threats.

The man who told Sports Illustrated in 2006 he doesn't eat red meat but might be tempted occasionally by Cheetos, was depicted in one phony Web photo wearing an orange Broncos shirt under his striped officials jersey.

As for the critical e-mail, he reportedly responded to every one.

"You can rest assured that nothing anyone can say can make me feel worse than I already feel about my mistake on the fumble play," read an e-mail, reportedly from Hochuli, that was posted on a SignOnSanDiego.com forum. "I'm very, very sorry."

Hochuli hasn't worked a Chargers or Broncos game since thanks to a schedule that was determined before the season, an NFL spokesman said. And he won't be working this Chargers-Broncos game (he'll be at Green Bay for the Lions-Packers game). But Hochuli, who has been the referee for two Super Bowls, has graded out well enough overall this year that he could end up working the playoffs.

Cutting it close

If only the Broncos could get there.

While all but one of the Chargers' losses were by a touchdown or less, five of the Broncos' wins were by a combined 14 points.

After the Broncos edged the Chargers by a point, they watched as Martin Gramatica's 43-yard field-goal attempt sailed wide right in a 34-32 win against New Orleans.

They got a crucial 6-yard run from Michael Pittman and three Matt Prater field goals to eke out a 16-13 win against Tampa Bay.

They broke Cleveland's heart again and ruined Brady Quinn's debut by scoring 21 fourth-quarter points, including Royal's 93-yard catch-and-run, for a 34-30 victory.

And against Atlanta, they needed three backs to reach 100 yards while holding Michael Turner to 81 in a 24-20 nail-biter.

"We're living on the edge," Cutler said after the cliffhangers.

Dive in

It's where they remain, on the precipice.

If they pull out the road victory (they've won three of the past four away games), Graham said he'll look back on coach Mike Shanahan's decision to go to pads in practice as the turning point.

"It brought more physical (play) to this team," he said.

They'll need it Sunday.

"We know it will be like a playoff atmosphere in San Diego. It will be us against everyone in that stadium. We'll be ready for it," Graham said.

They've got nothing to lose, except the West.

INFOBOX

Did you know?

As the Broncos-Chargers showdown nears Sunday night for the AFC West title, here are a few facts to consider.

* Both teams lost to Carolina, Miami and Buffalo but beat the New York Jets and Tampa Bay.

* Both teams overcame a stretch of three consecutive losses.

* Both teams struggled at home (Denver lost four, San Diego three).

NUMBERS GAME

13 turnovers forced by the Broncos, who are minus-15 in giveaways/ takeaways.

13 interceptions by the Chargers, who are plus-2 in giveaways/takeaways.

5 field-goal attempts missed by San Diego kicker Nate Kaeding.

5 field-goal attempts missed in the past five games by the Broncos' Matt Prater.

THEY WROTE IT

"I am going to give a weather report for Denver come Sunday: Partly to mostly dismal with intermittent to heavy showers of wrath & pain!"

Post on SignOnSanDiego.com

"When I'm in San Diego this Sunday nite I will remind all of the Charger fans that we (Denver) have two SB trophies and SD has Norv Turner . . . we have have two SB trophies and SD has NEVER been able to close the deal!"

Post on RockyMountainNews.com