ENGLEWOOD, Colo. -- Early on in training camp Denver Broncos cornerback Chris Harris Jr. said he could see the team’s re-vamped offense, with Case Keenum as the unquestioned starter at quarterback, “putting up points, at least 30 a game."

So while Saturday night’s preseason opener was just one outing, and just a short cameo from the offensive starters at that, the fortunes of the Broncos’ first- and second-team offenses will be at least cause for pause in the coming days.

In two series of work, Keenum completed only one pass and the starters had just nine total yards in two three-and-outs. And while the Broncos eventually scored 28 points, the first- and second-team offenses combined for just seven of those points, on an abbreviated 30-yard scoring drive following an interception.

“We didn’t move the ball at all,” said Broncos coach Vance Joseph of his starting offense. “… So, disappointing obviously. You want guys to go out there and at least have a decent drive, but we didn’t do that.”

Joseph didn’t push it and stuck with the plan to only allow his starters two series. Paxton Lynch played seven possessions as the No. 2 quarterback with largely the second-team offense and the group struggled much of the time as well. Lynch was 6-of-11 for 24 yards with a sack and an interception.

The Broncos didn’t have a drive go more than five plays when Lynch was in the game -- six of the possessions went three or fewer plays -- and five of the possessions went for 5 or fewer yards as they worked through a variety of formations and personnel groupings. They didn’t get their initial first down in the game until there was 5 minutes, 47 seconds remaining in the first half.

“It’s just frustrating not playing well and you don’t have a chance to bounce back from it,” Keenum said of his short night. “You have to sit there and root your other teammates on.”

Joseph and offensive coordinator Bill Musgrave have spent much of the offseason talking about creating matchups and finding the run-pass balance that works for the personnel the Broncos put on the field. Keenum has been exceedingly accurate in training camp and even following Saturday’s game, the Broncos players were quick to maintain their optimism about what things will look like when there is game-planning in the regular season.

Still, for a team that struggled to protect all of three of its starting quarterbacks last season, had too many ill-timed penalties and uneven play overall behind center, it certainly wasn’t the unveiling of the new playbook they wanted. Even in a game that didn’t count.

“… You can’t have negative plays, can’t have the penalties,” Keenum said. “Those things set you back. We never got into a rhythm, never got that first first down and got going. Yeah, it definitely left me wanting more. I’m sure that’s how a lot of them felt.”

Keenum’s only completion came on the first play from scrimmage and the Broncos’ first penalty came on the second play. Lynch’s first pass attempt was intercepted and his second attempt went for no gain.

Joseph called Lynch’s performance “up and down” and the night could be summed up in that the fans who remained in the stands in the fourth quarter were chanting No. 3 quarterback Chad Kelly’s name as the Broncos’ third-teamers handled the Vikings’ defensive reserves. Kelly, who Joseph has said could get a look with the No. 2 offense in the practices to come, finished 14-of-21 for 177 yards with two touchdowns and an interception.

"Obviously, Case is the starter, so that’s my main concern,” Joseph said. “Chad has played well. He played well (Saturday), outside of the one interception, which led to a score for those guys. He is a guy that plays with a lot of confidence. That’s a good deal.”

The Broncos will get another look at their progress this week as they will practice against the Chicago Bears for two days leading up to Saturday night’s game between the two teams. There will be plenty of the usual it’s-just-one-preseason-game to explain what happened against the Vikings, but for a team that continues to say it will be better than many others believe there is plenty of work to be done.

“We have some good film, have some stuff to learn,” Keenum said. “And I’m excited to get back on the field this week against the Bears.”