DENVER (AP) -- Vance Joseph watched his team go from cruising along to a nearly colossal collapse over a nightmarish fourth quarter.
In the end, the newest Denver Broncos head coach was presented the game ball to go with all that unexpected late-game stress.
Joseph and the Broncos walked away a 24-21 winner over the Los Angeles Chargers on Monday night when Shelby Harris sliced through and blocked kicker Younghoe Koo's 44-yard field goal attempt with a second left.
"It's a hard league," said Joseph, whose team led 24-7 heading into the final 11 minutes.
No arguments from Anthony Lynn, who also was making his head coaching debut for the Chargers. It marked the first time two black head coaches worked their first NFL game against each other.
This was more of the same for the Chargers, a team that had five losses by four points or less last season.
"There are some things we could've done better to help ourselves," Lynn said.
Philip Rivers caught fire in the fourth quarter and guided the Chargers into range for a game-tying field goal.
Koo nailed it -- but Joseph called timeout just before he kicked. The rookie coach wanted to ice the rookie kicker.
Koo made good contact on the second attempt as well, but Harris was right there to block it with the right side of his hand.
"I'm going to be real with you: I have no clue what happened," Harris said. "I felt it. I just couldn't tell you where I felt it. It just happened."
The Broncos held Rivers and the Chargers offense to 115 total yards heading into the final quarter. But the Broncos didn't do themselves any favors with drives down the stretch ending like this: Interception (bounced off a defender's foot), fumble (Jamaal Charles), missed field goal (Brandon McManus, who just signed a new deal) and a punt.
That opened the doors for Rivers.
"We just waited too long to get started but then you could feel it," said Rivers, who threw for 132 of his 192 yards passing in the final 15 minutes. "You could feel it in the place."
Joseph kept his team focused by imploring them to remember it wasn't over. He was right.
"Everybody in the stands was getting ready to leave," Broncos receiver Emmanuel Sanders said. "We thought it was over and then the next thing you know it's a three-point game and they're getting ready to tie … and it's about to go into overtime."
Harris' heroics saved the Broncos from blowing a 17-point fourth-quarter lead for just the second time in their history.
FOWLER'S TDS:Bennie Fowler doubled his career touchdown total with a pair of TD grabs, hauling in Trevor Siemian's passes from 5 and 6 yards out.
"It was amazing. It felt great to go out there and get two touchdowns. I had two touchdowns in my career coming into the game so it feels good. I'll continue to build on that," Fowler said.
Fowler was put on notice when the Broncos drafted wide receivers Carlos Henderson and Isaiah McKenzie, but he earned the job as Denver's No. 3 pass catcher behind Sanders and Demaryius Thomas.
"I've been on the same page with Trev now for three years. He's part of the reason I made the team as an undrafted rookie so I appreciate him," Fowler said.
TIGHT END TRIO: The Broncos got the most out of their tight ends, who combined for 98 yards receiving.
A.J. Derby had three catches for 34 yards, Virgil Green one for 44 and Jeff Heuerman two for 20.
"Awesome," Joseph said. "All three guys caught balls for (nearly) 100 yards. That's Mike McCoy's offense. Everyone gets an opportunity."
DUD OF A DUO: Antonio Gates is still tied with Tony Gonzalez for most touchdowns (111) in NFL history by a tight end. The Broncos limited him to two catches for 17 yards and held him out of the end zone. They also held Hunter Henry without a catch.
"We have to get those guys targets as coaches," Lynn said. "We have to do that. They were double-teaming Antonio, but we have to find those guys. We have to find those guys and dial up plays for them. They're too good of players not to get targeted, so that was on us."
REPEAT PERFORMANCE:This game was reminiscent of last season's opener, when the Broncos beat Carolina as Graham Gano missed a 50-yard field goal with 4 seconds left.
"That's how they're going to be -- going to be like that all season," Broncos cornerback Chris Harris Jr. said. "We know we're a better team than we displayed in that third and fourth quarter. We'll fix that and be able to finish the game even better."