The Denver Broncos will begin their preseason Friday in Atlanta without starting quarterback Bo Nix — but with plenty of other intriguing storylines to follow.

Here are four things to watch:

Ehlinger’s big audition

When Nix suffered a broken ankle at the end of last season’s divisional round playoff win against the Buffalo Bills, backup Jarrett Stidham was thrust onto the biggest stage of his career. Had he shined in the AFC Championship Game — and then again, perhaps, in the Super Bowl — he could have turned himself into an attractive option for teams in search of a new starter this past offseason. Of course, it didn’t go that way for Stidham, who turned the ball over twice in the 10-7 loss to the Patriots in the AFC title game. Of his 133 passing yards on 31 attempts, 52 came on one throw to Marvin Mims in the first quarter.

Now, for the first time since becoming Denver’s backup quarterback in 2023, Stidham has real competition for the job. It comes in the form of Sam Ehlinger, a sixth-round pick of the Indianapolis Colts who is entering his second season with the Broncos. Ehlinger had a chance to return to the Colts late last season with Indianapolis in desperate need of a quarterback — they eventually turned to 44-year-old Philip Rivers, who hadn’t played an NFL game in five years — but he chose to remain in Denver and continue developing under Payton and Davis Webb, now the team’s offensive coordinator. Giving himself a full year with the system has helped Ehlinger make a clear jump during his second training camp in Denver. Payton said Ehlinger’s “spaghetti sauce” is his ability to buy time when plays break down, a similar profile to Nix.

“He can move,” Payton said. “I like how he’s looked. You don’t get to appreciate a quarterback like him until you’re out there, and everyone’s on the sideline, and then the ball moves. Sometimes it’s harder to appreciate that when you’re scripting plays, but he has a great pedigree. I know he likes it here. I think he’s done a lot of good things. I saw him in college (at Texas) win a lot of games, beat Georgia in New Orleans. He’s fitting right in.”

Stidham will start Friday’s game and play the first half. Ehlinger will operate Denver’s offense in the second half. With Nix scheduled to play at least some time in the next two preseason games, Friday will mark the most extensive audition in the race to be his backup.

Can Coleman be backfield’s missing piece?

J.K. Dobbins sprinted from side to side behind the play Wednesday as Denver’s fellow starters conducted a walkthrough. The veteran running back missed part of a practice earlier this week while dealing with what Payton described as a soft-tissue injury, but his presence in pads during the two days that followed was evidence that Dobbins isn’t dealing with anything significant. Still, it would be a surprise to see Dobbins suit up for Friday’s preseason opener, and that will mean even more time on the field for rookie fourth-round pick Jonah Coleman.

The Broncos struggled in the run game last season after losing Dobbins to a season-ending foot injury in Week 10. RJ Harvey, then a rookie, showcased explosive ability and became a consistent threat as a receiver out of the backfield, but he couldn’t match Dobbins’ down-to-down consistency. Coleman has shown during training camp practices a natural feel for navigating the thin spaces inside the tackles. Payton, when asked to name a player who stood out to him in a positive way during the first two weeks of camp, pointed to Coleman.

“You don’t feel rookie with Jonah,” said Payton, who noted that Coleman’s experience in a college system at Washington gave him extensive responsibilities as a pass protector, which has blunted what can be a steep learning curve for young backs entering the NFL.

Harvey, too, has had a nice camp, showing even more growth as a receiver and with the pass-protection duties that were somewhat foreign to him coming out of Central Florida last year. But the big question Friday will center around Coleman and whether the rookie can be the missing piece for a running game that must improve for Denver to reach new heights offensively.

Who will earn a roster spot at linebacker?

Starting inside linebackers Alex Singleton and Justin Strnad played in a combined 32 games last season alone. The five other players at that position on Denver’s training camp roster — Levelle Bailey, Karene Reid, Jordan Turner and rookies Red Murdock and Taurean York — have played in 30 combined games across their respective careers. While many of the depth spots on Denver’s roster are filled by players with extensive experience, inside linebacker is an exception. Much of the time Bailey, Reid and Turner have spent on the field in regular-season games has come on special teams, so this preseason will be a pivotal proving ground as the Broncos identify which player is potentially ready to step into a key role defensively.

“I’m kind of excited to see, both from (special teams coordinator Darren) Rizzi’s perspective and then from a defensive perspective, who are those other two players?” Payton said.

Reid, who made the initial 53-man roster last season as an undrafted free agent but missed much of the year due to injury, and Bailey have worked with the second-team defense during training camp. Murdock, the final pick of April’s NFL Draft, and York, a priority undrafted free agent, have run with the third team. That pecking order, though, is lightly etched in pencil. It will be particularly intriguing to see whether Murdock, who forced a record 17 fumbles during his college career at Buffalo, can pop from a playmaking perspective after putting together his best stretch of practice last week.

“Red, from Day 1, has made every call cleanly, but he was kind of over-processing things,” defensive coordinator Vance Joseph said. “Now, he’s playing fast and punching the ball out.”

Can Barron flash to start Year 2?

Nearly 18 months after being selected by the Broncos with the 20th overall pick in the 2025 NFL Draft, Jahdae Barron is still a player without a starting role. The former University of Texas standout competed for the nickel role in camp as a rookie, but Ja’Quan McMillian convincingly won that job — and then turned in a performance that established him as one of the NFL’s best players at that position. At outside corner, Riley Moss made leaps as a starter opposite Pat Surtain II in 2025 and has been one of Denver’s best players in camp this month.

Both McMillian and Moss, though, are entering contract years. Whether the Broncos extend one or both of those players could hinge on where they view Barron fitting into the picture. That makes this a pivotal preseason for Barron. If Moss and McMillian are both healthy this season, Barron’s role in Vance Joseph’s defense will largely come in the dime spot within DB-heavy packages like it did last season. Barron has worked there, outside and some in the nickel during camp. His versatility makes him a valuable reserve.

If Barron plans to be more than that — this season, yes, but particularly beyond — he needs to put together a strong preseason.

“The game is slowing down for him,” said Rob Livingston, Denver’s defensive passing-game coordinator. “Put yourself in a rookie-in-the-NFL’s shoes. All of a sudden, you’re guarding Travis Kelce as opposed to playing him in a video game. Obviously, he was uber successful in college in a big program and played with big-time names, but it’s different here. … Like everybody, he’s got a long way to go. We’re working through it every day, but he’s another guy who is immensely talented. Once he figures it out, the sky’s the limit.”