SAN FRANCISCO -- Though the full complement of starters didn't see much playing time Thursday evening at Candlestick Park, the Broncos still got a number of firsts out of the way in the 2013 preseason opener.

Peyton Manning's first pass -- a completion to tight end Julius Thomas. The defense's first third-down stop -- which forced a 32-yard field goal. Trindon Holliday's first electrifying kickoff return -- he picked up 30 yards on his first touch.

While the club's first points didn't come until most of the starters were out of the game -- Shaun Phillips returned a second-quarter fumble caused by Nate Irving for a touchdown -- the team got, as Manning said he wanted before the game, a chance to execute in "a mix of situations."

Most of the Broncos' starters saw about a quarter of action against the 49ers, though a few players -- like Manning, cornerback Champ Bailey and linebackers Von Miller and Wesley Woodyard -- stayed in the game for just one series.

Manning finished the game 2-of-4 for for 13 yards, helping the offense pick up two first downs before the drive stalled near midfield thanks to some pressure by 49ers linebacker Aldon Smith.

"That's a very good defense we're going against and it's typical of a first game," Head Coach John Fox said at halftime.

Both of his Manning's completions went to a Thomas -- Julius first and wide receiver Demaryius later in the seven-play drive. Running back Ronnie Hillman picked up 9 yards on his three carries in the series.

The offense started in a three-receiver set, with Demaryius Thomas, Eric Decker and Wes Welker in alongside Julius Thomas at tight end and Hillman at running back with Manning at quarterback. The starting offensive line consisted of Chris Clark, Zane Beadles, Manny Ramirez, Louis Vasquez and Orlando Franklin, who had injured his hip earlier this week in training camp practice.

As for the defense, the starting unit comprised of Derek Wolfe, Kevin Vickerson, Terrance Knighton and Robert Ayers on the defensive line, Woodyard, Stewart Bradley and Miller at linebacker, Bailey and Chris Harris at cornerback and Rahim Moore and Duke Ihenacho at safety.

Though the 49ers picked up a first-and-10 at the Denver 20-yard line, the defense held strong. First, Bradley made a stop for no gain on a run, then the 49ers committed a false-start penalty. A tackle of LaMichael James in the backfield by Woodyard made it third-and-16, and though quarterback Colin Kaepernick found a receiver for a 12-yard gain, the third-down stop forced a 32-yard field goal, the first points of the game.

"I think defensively we played pretty good," Fox said at halftime. "Offensively, we struggled a little bit – mostly, in particular, (with) blocking."