ORCHARD PARK, N.Y. — When halftime arrived at New Era Field, the Broncos still hadn't scored a point.

At the break on Sunday against the Bills, Denver had allowed 144 rushing yards, totaled fewer than 100 yards of their own and turned the ball once as they neared the red zone.

And still, Denver had a chance.

The Bills led just 6-0 at halftime, as the Broncos' second-ranked red-zone defense held stout. Somehow, the Broncos were in position to take the lead with a single touchdown drive.

Denver never got that drive it so badly needed.

The Bills scored a touchdown on the opening drive of the second half to push the lead to 13-0, Denver's offense recorded just three points and 40 more yards in the second half and the Broncos fell to 3-8 on the season with a 20-3 loss to the Bills.

"We just got whipped today," said Von Miller, who recorded his sixth sack of the season when he took down Josh Allen in the first half. "[They've got] a good team, have a good defense. They play good on offense too. We just got whipped in all three phases. There's not much else to say, just [have] to keep it real, and just the reality of it is we got whipped. I don't think that changes our energy and how we prepare though. I don't think it changes our day-to-day energy. We've still got to stay on to that. And I know we'll stay onto that."

The Broncos have lost back-to-back games on the road, and this loss hardly seemed in doubt after the opening frame.

Buffalo finished the game with more than 400 yards of total offense, and the Bills' defense picked off Brandon Allen once and sacked him on four occasions.

With a steady dose of no-huddle offense and a smothering defense, the Bills took control of the game early and hardly looked back.

Safety Justin Simmons briefly gave the Broncos a chance to take the lead, as he intercepted Allen's pass with 4:13 to play in the second quarter. Simmons returned the ball to the Buffalo 32-yard line, but an illegal blindside block penalty on Kareem Jackson pushed the ball back to the Denver 47-yard line.

Simmons' interception was his third of the season, which ties his single-season career high he set in 2018. Simmons has the fourth-most interceptions (10) by a Broncos safety through their first four seasons.

Denver moved the ball to the Buffalo 25-yard line on the ensuing drive, but Denver's Allen threw an interception to Tre'Davious White to end the drive. Allen targeted Courtland Sutton on the play, but Sutton ran a comeback route, while Allen appeared to expect him to keep running up the seam.

"It's just on me," Allen said. "Called the right play, thought the wrong thing. Thought he was going to keep going. Courtland did exactly what he's supposed to. He stopped on the route, and I threw it like he was going to keep running and made a poor decision there."

Added Head Coach Vic Fangio: "It was critical, obviously. We were in field-goal range, with the wind at our back, and it took points off the board — at least three."

The Broncos did not get any closer to the red zone. The team went all 60 minutes without a trip inside the Buffalo 20-yard line.

Despite the Broncos' first-half struggles, Denver remained in the game at halftime and trailed just 6-0. The Bills, though, posted an eight-play, 59-yard touchdown drive to start the second half and extend the lead to 13-0. The Broncos were unable to cut the lead to one possession during the rest of the game.

"Actually, early on it was kind of OK, considering the conditions and the good defense we were going against," Fangio said of the offense. "But at some point there, we just stopped moving it totally and they kind of smothered us. It was a problem, obviously, and one that we need to get rectified somehow."

The offense, in general, failed to generate much momentum. A week after recording 113 yards on five catches, Sutton tallied just one catch for 27 yards on eight targets.

"He tweaked his ankle early in the game and kept playing, but I do think it affected him some," Fangio said of Sutton. "I just think their whole defense as a whole just kind of whipped us, so it left the opportunities for everybody down to a minimum."

Allen, meanwhile, completed 10-of-25 passes during the game for 82 yards, an interception and a 32.4 quarterback rating.

Fangio said he had not given any thought to whether rookie quarterback Drew Lock would play against the Chargers in Week 13. The Broncos must activate Lock ahead of the team's Week 14 game in Houston, or else Lock will revert to injured reserve for the remainder of the season.

Allen said he hopes to continue to start at quarterback.

"Obviously I want to play," Allen said. "I want to be part of the solution. That's not up to me, so I'm going to work like I'm going to play next week."

The Broncos have scored just six points over the last six quarters, dating back to a Week 11 game against the Vikings.

Denver's opening drive also appeared promising, as Allen found Sutton for the receiver's lone catch of the day. Guard Dalton Risner, however, was whistled for an unnecessary roughness penalty later in the drive, and the Broncos failed to capitalize off their largest gain of the day.

The offense never truly improved, as Denver gained just nine first downs, tallied 134 total yards, went 2-for-11 on third down and turned the ball over on the edge of the red zone. Forty-eight of those yards came on the Broncos' first second-half drive, which culminated in a 45-yard Brandon McManus field goal.

Denver's defense held the team within striking distance for most of the game, but Buffalo's touchdown drive to begin the third quarter broke open the game — and the Bills only piled on from there.

Wide receiver John Brown, who led the AFC in receiving yards entering Week 12, caught a 34-yard touchdown pass early in the fourth quarter to deliver the final margin.

The Broncos have now been outscored 40-0 in the fourth quarter of the last five games.