DENVER -- Broncos quarterback Drew Lock stood in front of the team's offense at halftime Sunday and said it was time for the group to "man up'' and that he had to be first in that line.

And in the 30 football minutes that followed that short speech, Lock erased two of the worst quarters he has played in his football life, the Broncos scored 28 second-half points -- 21 of those in the fourth quarter -- and Denver snatched a 31-30 victory from the Los Angeles Chargers on the game's final play.

"I just got up in front of the offense and said, 'Listen, it's so easy for us to come in here and yell and scream and get mad about what we're doing bad, but we just need to man up, and when the plays come our way, we need to make them, myself included. I'm not yelling at y'all, I'm obviously talking to myself right now, screaming to myself right now,''' Lock said. "And that's exactly what we did.''

Lock, coming off a 24-of-40 passing, two-interception day in the 27-point loss to the Kansas City Chiefs, had been bombarded with criticism from outside the team's complex in the days leading up to Sunday's game. Criticisms about his mechanics, a possible regression and concerns that even in the Broncos' Oct. 18 win over the New England Patriots he had been just 10-of-24 with two interceptions.

And Sunday, it all looked to be boiling over. Trailing 14-3 and with 60 net yards on offense, the Broncos were booed off the field by most in the 5,700 on hand; Lock was just 9-of-15 passing and still without a touchdown throw since the season opener. That was when the second-year quarterback said a wave of perspective hit him.

"Maybe people had opinions of us in six games, with three different quarterbacks, multiple O-lines, guys on defense getting knocked out,'' Lock said. "I think people just like to make opinions and jump to it quick, and I hope we can keep proving them wrong.''

"We're a bunch of fighters, OK? We play hard, we play physical, we play for each other, we're going to play as a team ... and we had to keep doing that,'' Broncos coach Vic Fangio said. "And we made a couple plays, got a couple stops and we got it turned. ... The best way you can get confidence is you have good play. You don't need to be sitting on some psychologist's couch to get confidence or read a book to get confidence, you've got to go out and play good.''

Most involved, including Lock, credited Phillip Lindsay's touchdown 55-yard touchdown run with just over six minutes left in the third quarter for popping things loose. Overall in the second half, the Broncos had 291 yards on offense, as Lock went 14-of-18 passing for 155 yards with three touchdowns in the fourth quarter alone.

"I've been here my whole life, and I know how it is,'' Lindsay said of the halftime boos. "This organization is a great organization, it's not used to having losing seasons, they're used to winning all the time. That's what I was used to growing up; that's what I want to get back to.''

Lock tossed the winning touchdown pass, a 1-yarder to rookie wide receiver KJ Hamler -- Hamler's first career touchdown catch -- with no time left on the clock. Hamler said following the game it was the first game-winning catch he had made in that kind of situation at any level of football.

It all came a week after notable defensive players such as defensive end Shelby Harris and linebacker Bradley Chubb had expressed plenty of frustration at the 10th consecutive loss to Kansas City. After that game, Lock had said Harris and Chubb had earned to right to say, "You need to pick your s--- up'' and said he would welcome them saying it to him if he wasn't pulling his weight.

"There was yelling after the Chiefs game, much-deserved and needed yelling,'' Lock said. "And it was kind of déjà vu coming in the locker room [Sunday at halftime], all the yelling and screaming, the offense isn't playing well, blah, blah, blah. ... But the plays came and there wasn't one that we turned down. ... It was awesome to be the quarterback of this team.''

The Broncos are now 3-4 following the team's third win in the past four games after an 0-3 start.