Their biggest gains ended with a lost fumble and penalty.

Their defense came up with a four-down, goal-line stand, only to watch from the sidelines as the opponents scored a touchdown, anyway.

An inept offense and poor special teams coverage left the Denver Broncos with an embarrassing, 21-0 loss to the Los Angeles Chargers here on a sweltering hot, late-October, Sunday afternoon before a sellout crowd of 25,288 at the StubHub Center.

The venue here was built for soccer and the Broncos responded by scoring nil. It was the first time since Nov. 22, 1992 that the Broncos were shut out, snapping a scoring streak of 394 regular-season games.

"I didn't even know that stat,'' said Broncos receiver Demaryius Thomas, who had an 81-yard catch-and-run in the third quarter called back by a controversial offensive pass-interference penalty called against him. "Getting shutout, period, in the NFL with the talent we have? It hurts. I can just speak for myself, I can't speak for anybody else. It hurts. I'm going to get better and hopefully everybody around me sees me working and we get better as a group.''

The previous shutout 24 years and 11 months ago was in a game also played in greater Los Angeles area. Tommy Maddox, filling in for the injured John Elway, threw two interceptions in a 24-0 loss to the Raiders.

In this shutout, Siemian completed 25 of 35 for 207 yards with one interception, which came on a fourth-and-6, what-do-you-have-to-lose play. He was sacked five times. Most of the blame will be directed at him as he's the quarterback. And to his credit, Siemian accepted responsibility.

"I gotta look at it, but obviously no rhythm and a lot of that fllas on me,'' Siemian said. "I thought especially early on I didn't do enough to get us going.''

Others in the losing locker room, though, indicated there is so much blame to go around, the physically battered quarterback doesn't deserve to accept any more than anyone else.

"People are going to blame whoever they want to. We're not worried about that,'' Thomas said. "We need to get better as a group. I've got Trevor's back, I don't care what anybody says. He's a warrior to me. He got hit so much and he got probably a broken nose, who knows? But I don't care what they say it's about what we've got to do as a group on offense to make us better.''

Siemian did not suffer a broken nose, although he did collapse like a human accordion after he took a vicious hit from Chargers' star pass rusher Melvin Ingram. Although, Ingram was flagged for roughing the passer -- changing his get-off-the-field sack into a Broncos first down -- Denver's drive was thwarted four plays later when Siemian fumbled the ball away after he was sacked from behind by linebacker Chris McCain.

There are two reasons to pull a quarterback from a game. One is poor performance. The other is to provide a spark. Siemain was gutsy through constant duress and he did hit his man whenever he had time and his receiver was open. But Broncos head coach Vance Joseph was asked if he thought about changing quarterbacks in hopes of changing momentum.

"No, I did not,'' Joseph said. "He's our quarterback. It's a two-score game for most of the game so why make a change when we're still in the game? ... We had three turnovers on the day which is way too many. We had a punt return for a touchdown, which can't happen. So it wasn't simply on Trevor. It was a two-score game and I felt, up until 5 minutes to go, it was a game we could have won.''

Everything looked great for the Broncos just eight days ago. Now, they are in serious trouble. They were 3-1 entering their bye week and are now 3-3. Not only did they lose to the heretofore 0-5 New York Giants and 2-4 Chargers by a combined 34 points, they have a daunting schedule ahead with games at 5-2 Kansas City, at 5-1 Philadelphia, and home against the defending Super Bowl-champion New England Patriots.

"You can't lose two games straight and not have any issues,'' said Broncos outside linebacker Von Miller, who had two sacks on Chargers' quarterback Philip Rivers to move into second place on Denver's all-time sack list.

"We're not blocking well,'' Joseph said. "We're not protecting well. We had some good plays called today with some guys wide open. ... It's puzzling. We had great weeks of practice. Offensive-line wise, we've run the ball very well up until two weeks ago. We have to coach better and play better, obviously.''

Hoping to run the ball against the No. 32-ranked run defense in the league, the Broncos managed just 69 yards on 3.6 yards per carry. C.J. Anderson was the Broncos' leading rusher with 44 yards on 10 carries. The Broncos had hoped to get Jamaal Charles more involved but he had just 2 yards on 4 carries.

It was a crying shame the Denver defense played with a team that was down, 7-0 after the first quarter.

Siemian started the game with a scramble left and wild heave downfield, where tight end A.J. Derby made a nice adjustment for a 23-yard gain. Derby fumbled the ball away, though, and the Chargers were in business at the Denver 45.

"Can't finish a play like that,'' Derby said. "I was trying to make extra yards and it's unacceptable, I can't be doing that. If they're going to be trusting me with the ball in my hands, I can't be doing that.''

A misdirection rollout pass from Philip Rivers to tight end Hunter Henry picked up 34 yards and the Chargers had first-and-10 at the Broncos’ 11.

Rivers then drew a pass interference penalty on Broncos safety Darian Stewart in the end zone, giving the Chargers first and goal at the 1.

Handoff to Melvin Gordon, who ran off left tackle Russell Okung. Nothing. Will Parks filled the hole from his safety position.

Handoff to Gordon off Okung. Nothing. Shaq Barrett blew up the play.

Handoff to Gordon up the middle. Nothing. Inside linebackers Todd Davis and Brandon Marshall filled in the gap.

Handoff to Gordon up the middle. Nothing. Davis and Parks and many others made the play.

An old-fashioned, four-down, goal-line stand by the Denver D.

And before it came back on the field, the Chargers scored.

"Can't quit,'' said Broncos defensive end Derek Wolfe. "We've got to fix the problems that we have. Everyone has to find a way to do more. Do more on Sundays. It's not like we're not practicing hard. We're practicing our butts off. We shouldn't be losing. We shouldn't be getting blown out. I don't know, I'm at a loss for words.''

The Broncos’ offense picked up one first down to get out of the hole, but a Riley Dixon punt was short and low so that Travis Benjamin fielded at on a hop at his own 35-yard line.

"A bad punt,'' Dixon said. "Got to put my team in better position to make a play. It was just a bad punt. Bad direction -- nothing good about it.''

Once Benjamin got through the first wave of Broncos’ chasers, he was up the middle before veering left in the open space. He went all the way for a 65-yard touchdown return.

"It was an awful punt, it was a line drive, hit the ground, it bounced right to the guy,'' Joseph said. "The coverage wound up suffering because of the punt being so bad.''

Eventually, the Denver D began to wilt beneath the burdens of carrying its poor offense and special teams, not to mention 90-degree temperature at kickoff. Rivers put together a 65-yard touchdown drive in the second quarter that was again sparked by a long completion to the tight end Henry, this time for 19 yards.

Rivers completed another 19-yard pass to Keenan Allen, who beat Bradley Roby on the play to set up another first-and-goal from the 1.

This time the Chargers didn’t try to run. Rivers flipped a pass to running back Austin Ekeler -- who hails from Eaton, Colorado and Western State -- and scooted in the left side of the end zone for a 14-0 lead.

The Broncos were about to rally in the second half when Siemian from his own 9-yard line rolled right and hit Demaryius Thomas on a deep comeback route. Thomas took off and wasn’t tackled until he reached the Chargers’ 1-.

An 81-yard gain for naught. On a late flag thrown by the official, Thomas was called for offensive pass interference.

"I don't think it was pass interference to tell you the truth,'' Thomas said. "You had some calls that shouldn't have been made and calls that weren't made and should have been made. That was one, as a receiver, I can't do anything except ... if I stopped to catch that ball, the DB would have ran into me. I don't know for 100 percent they're going to call it on them so all I did was move, swipe with my left -- it's not a pass interference -- and they called it.

"It was a dagger. It was a big play. It was something we needed. It was a spark. We didn't have it in the first half. We didn't have it the whole game. You never know, it could have changed the whole game.''

Instead, it was the Chargers who scored the next touchdown on a slant pass from Rivers to the speedy Benjamin, who took it in for a 42-yard touchdown with 5:42 remaining.

All that was left from there was for the Broncos to finish up their failed attempt to score in a 60-minute for the first time since Elway's backup Maddox was harassed by the likes of Chester McGlockton and intercepted twice by Raiders defensive back Terry McDaniel.

"It's tough, adversity, especially in the National Football League,'' Miller said. "It always feels the same. It always feels like the end of the world. Your back is against the wall -- you have to do something right now. That is OK. We will go to work tomorrow, practice great and our breaks will come.''

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