First, look to special teams.
Three of the primary candidates to handle kickoff returns are undrafted rookies: wide receivers Bralon Addison, Kalif Raymond and Mose Frazier.
All are in the mix, along with incumbent punt returner Jordan Norwood, to fill the positions held for much of last season by Omar Bolden, who left for the Chicago Bears in free agency.
Raymond got the jump on the position by displaying shiftiness and good vision on returns during OTAs. At a listed weight of 160 pounds, the former Holy Cross sprinter is the lightest player on the roster by a 20-pound margin, but plays on offense and special teams with a fearless abandon and a willingness to go into heavy traffic and use his quickness to break through.
"He's got some speed. That's the big key with him," Special Teams Coordinator Joe DeCamillis said. "He's a guy that also catches the ball well. That's the first thing you look at as a punt returner is how they track the ball and how they catch it. He does a really good job of that."
Frazier got more work on returns later in OTAs and was "a little bit of a surprise" during OTAs, DeCamillis said. Frazier should see repetitions throughout training camp and the preseason. His timing with Paxton Lynch from their days together at Memphis also enhances his chances, given what his offensive role could be.
Addison has the most high-level college experience on returns, coming from Oregon, but missed nearly all of OTAs because of his school's academic calendar, so he will have the most catch-up work ahead of him.
"I thought I did okay," he said after his work during the last week of OTAs. "Definitely a lot of room for improvement. I've got a lot of time to catch up and a lot of making up to do just because I was behind being out."
Nathan Theus also has a shot at roster spot; he will battle with Casey Kreiter, a veteran of two training camps with the Dallas Cowboys, for the long-snapping job.
But for roles on offense or defense, the undrafted player best positioned to grab a roster spot is tight end Henry Krieger-Coble.
The Iowa product saw plenty of first-team repetitions during team and seven-on-seven periods of OTAs because of injuries to Virgil Green and Jeff Heuerman. He became a reliable target; he has some of the best hands on the team, and is outstanding at reaching out and plucking passes with his arms extended and without breaking his stride.
Just as important as what Kreiger-Coble does on the field is what he accomplishes in the weight room.
"The big thing for him is going to be getting bigger and stronger," Head Coach Gary Kubiak said during OTAs. "I don't know how much ground you can make up between now and training camp, but that's going to be the key for him in his career. Can he get a little bit bigger?"
Krieger-Coble said the Broncos want him at 245 pounds -- five pounds below what he was at Iowa. But they want his weight to be from lean muscle.
"You go in there and do what they tell you, because they know exactly what's right for you," he said, "and then go in and work your hardest the whole time."
Kubiak also pointed to outside linebacker Kyle Kragen, the son of former Broncos nose tackle Greg Kragen, as an undrafted rookie who impressed during OTAs, but the coach added that it was hard to single out one or two players.
"They're all ready to compete, I know that," Kubiak said.
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