Damarri Mathis’ professional career got off to a slow start. The fourth-rounder out of Pittsburgh only saw the field in two of of his first four NFL games and played sparingly.

Then, in Week 5, Ronald Darby went down with a torn ACL in the first half against the Colts and Mathis took his spot as the starting boundary cornerback across from Pat Surtain. Matt Ryan threw his way nine times and completed all nine of the passes.

Mathis earned his first career start the next week against the Chargers. He gave up six completions on nine passes his direction. The bigger story was the four pass interference penalties. Only one player, Cleveland’s Martin Emerson, was called for more pass interfence penalties all season than Mathis was called for in that single game.

But Mathis started every game the rest of the season except for the finale against the Chargers which he missed with a concussion, and he held his own. He gave up 33 completions for 266 yards and two touchdowns on 58 targets. Those numbers were good for an 80.1 passer rating when targeted.

Of the 152 NFL cornerbacks who played at least 100 coverage snaps last season, that mark would have ranked 37th.

Now, the 24-year-old figures to be in the driver’s seat for the Broncos’ second boundary cornerback position, but he’ll have some competition.

The Broncos selected Riley Moss out of Iowa in the third round of April’s draft. They signed 26-year-old Tremon Smith, who started two games for the Texans last year. Ja’Quan McMillian spent most of his rookie season on the Broncos’ practice squad, but started the season finale against the Chargers when Mathis was hurt and played well. 

Mathis is a heavy favorite to be the starter, and it may take a disastrous training camp for his Week 1 starting job to be in question.

But the third boundary cornerback job is very much up for grabs.

Smith could provide a steady hand at the position, given he has five years of NFL experience, including a handful of games as a starter. He has the speed to hang with modern receivers. He was a ballhawk in college and earned the first two interceptions of his NFL career last season, but he lacks the upside of the younger guys, given he hasn’t been able to break into a starting role with the Chiefs, Packers, Colts or Texans. Coming from Central Arkansas, a transition period was always anticipated for the sixth-rounder, but five years is longer than you’d expect. Smith will have a special teams role, he’s one of the league’s most explosive returners, but a role on the Broncos’ defense will be tougher to find.

The younger corners, Moss and McMillian, provide massive upside. Either player could turn into a longterm starter in the NFL. 

But Moss comes from an Iowa defense that almost exclusively plays zone coverage. In Cover 3, Moss might be ready to see the field on Day 1. After only playing about 17% of his snaps in man coverage during his college career, according to Pro Football Focus’ tracking, Moss may not be ready to play at an NFL level. Manning up against Davante Adams, Mike Williams or Keenan Allen in AFC West games would be a challenge after not playing much man coverage since high school.

McMillian’s schematic limitations are probably more concerning in the long term. He ran a 4.55-second 40-yard dash in last year’s draft process, which means he could struggle to keep up with receivers in man coverage and could struggle against speedy receivers in deep zones. But McMillian might have the third-best ball skills on the defense behind Pat Surtain and Justin Simmons. He picked off 12 passes in college, includin five passes in his senior year, which ranked third in the nation. He could have had a pick-six in his NFL debut but the officials called the pass I compete in a controversial call. McMillian had a couple of other solid plays on the ball, too.

In a Cover 2 scheme, McMillian could be the Josh Norman-type of corner who can pounce on throws in flat zones and force turnovers and incompletions. Even a Fangio-style defense like the Broncos ran for the past four seasons could have a great role as an aggressive ball hawk close to the line of scrimmage. But McMillian will have to prove that his lack of long speed won’t be exploited in Vance Joseph’s aggressive, single-high system. 

On the flip side, the ability to break on passes on create turnovers could be the most important trait for a cornerback who starts across from Surtain. Teams will be wary of throwing the ball toward the All-Pro, which means the corner manning the opposite side of the field will be playing a high-volume position. McMillian might be the best option to take advantage, but Moss probably wouldn’t be far behind him. At Iowa, Moss excelled at reading the quarterback’s eyes, and he finished his career with 11 interceptions. 

Moss has speed and size on his side. McMillian has a slight edge in both ball skills and tenacity. At least for now, Mathis also has the edge in versatility.

Mathis has them both in speed and versatility. Most importantly, Mathis has proven that he can already play at a mediocre level (which isn’t a bad thing for a rookie) and you could make the case he’s proven he can be an above average starter if you’re willing to throw out the early portion of last season.

Heading into training camp, Mathis has a very strong hold on the second starting cornerback job. He could blow his lead, but that seems unlikely. At least one of McMillian and Miss should get extensive opportunities at some point in the season, and if one of them plays well then Mathis might start feeling the heat. 

The real competition for CB2 will probably come next offseason… unless Mathis becomes a top-tier second starter this season.