DENVER -- It took Denver Broncos rookie quarterback Drew Lock all of 10 or so football minutes of his first career start Sunday to learn an important lesson -- get the ball to Courtland Sutton and things could work out just fine.

And on a day with some growing pains along for the ride and certainly more on the way, Lock threw two touchdown passes to Sutton, and Sutton also forced a pass interference penalty in the game's closing seconds as the Broncos defeated the Los Angeles Chargers 23-20 on Brandon McManus' 53-yard kick.

"I think it was a good start for him,'' Broncos coach Vic Fangio said. "Was it, uh, did we light up the scoreboard? No. Did we get a ton of first downs? No. I think we only had 11 first downs ... but I think there's promise there, I'm just not ready to put him in Canton yet ... it's something he can build upon.''

Lock finished 18-of-28 passing for 134 yards with the two touchdowns to Sutton to go with an interception. The rookie became the seventh quarterback to start a game for the Broncos since Week 9 of the 2017 season and the franchise's first quarterback to see the Broncos win in the first start of his rookie season since both John Elway and Gary Kubiak did so in 1983.

Lock was largely enveloped in a game plan to limit his exposure to the Chargers' pass rush, as he threw both of his touchdown passes in the first quarter. Lock also enjoyed the benefits of some quality field position, as 10 of the Broncos' points came following Chargers turnovers and the short fields that came with them -- those two Broncos scoring drives were 18 and 8 yards, respectively.

The Broncos later had a 21-yard field goal drive in the fourth quarter after the Chargers had missed a field goal of their own.

"I think he did fine," Fangio said. " ... I think he handled himself well during the game. Calling the plays in the huddle, not looking like the situation was too big for him, didn't think he was nervous ... he should keep improving.''

But it was a tough start, as the Broncos, who had scored more than 16 points in a game just four times this season coming into Sunday's affair, had a quick three-and-out on their first possession, and Lock admitted to feeling some nerves.

"That first drive, I came off the field and said, 'I'm sorry about that one, I'm good, let's go roll now,'" Lock said. " ... My heart was beating a little fast; after that first drive, I was ready to go.''

On the second possession, Lock hit two of his first three attempts as the Broncos methodically moved the ball. Eventually, facing third-and-8 from the Chargers' 26-yard line, Lock did what the Broncos hoped he could do for quite some time: Lock told Sutton to run the fade, and Sutton made a diving, one-handed catch for the touchdown.

"'Amazing' is not even a good word to describe how good a catch that was,'' Lock said. "He's been making plays left and right for us, and I think he's a top receiver in this league for sure.''

Asked if Sutton, who also had caught Brandon Allen's first career touchdown pass three games before on a leaping grab against the Browns in the same end zone, was a luxury for a rookie quarterback, Fangio said:

"That's a luxury for any quarterback, not just a rookie quarterback. Courtland can make those plays, 50-50 ball and he got the ball.''

Lock threw a 5-yard scoring pass to Sutton on the Broncos' next possession, and later with the game on the line in the closing seconds, Lock made a throw up the right sideline toward Sutton as Chargers cornerback Casey Hayward was flagged for pass interference.

The penalty gave the Broncos the ball on the Chargers' 35-yard line with three seconds to play. McManus made the game winner to close out the win.

Fangio said that before Lock's final pass attempt, there was some talk on the headset about Lock taking a knee and sending the game to overtime, as well as trying a pass over the middle and then calling a timeout.

"I said no,'' Fangio said. " ... I said, 'Let's go down the sideline and see what happens.'"

So, Lock's 11 yards passing in the second half, and his first career interception, will all be fodder for the days to come. For one day, for those shivering in the seats, it was all about Lock and what could be.

After all, Lock had been on injured reserve since the start of the season because of a right thumb injury and was officially moved to the Broncos' roster Saturday. Fangio said he told Lock on Friday that he would make the start, though Fangio did not publicly announce it before Sunday's game.

"In my mind, Wednesday and Thursday he had to have good enough practices to do it,'' Fangio said. "And I think he did ... I don't know why (he didn't announce it), playing silly games."