ENGLEWOOD, Colo. -- Denver Broncos coach Gary Kubiak will often admit what he's worrying about as the season rolls on. But when Kubiak calls something a "concern," that's a front-burner issue that demands attention.
When Kubiak was told at one point during the Broncos' win over the Jacksonville Jaguars Sunday that Juwan Thompson was the only available running back, it was a concern. As it was when the Broncos landed back in Denver later that night and there was a possibility the Broncos would have to move running back Kapri Bibbs to injured reserve because of an ankle injury suffered before halftime.
"I know I just have to pick it up," said rookie Devontae Booker, who is the only Broncos back to play in every game this season. "I feel like I have to get better from what I've done lately, even (Sunday)."
The Broncos have had various difficulties lead to the erosion of their running game this season. They've suffered multiple injuries on the offensive line, they've struggled to find consistency even when all of the starters on the line are available and their top running back -- C.J. Anderson -- is on injured reserve after knee surgery in late October.
And just as Bibbs flashed the potential to shake the Broncos' run game out of the doldrums Sunday with 49 yards on his five carries -- he had runs of 24 and 13 yards on the offense's only touchdown drive of the game -- he suffered his injury. The Broncos officially moved him to injured reserve Monday.
"I felt like I was getting ready to do some good things," Bibbs said. "You always want to help your team."
"Kapri gave us a little boost," Kubiak said. "He came in and ran really well."
The Broncos added Justin Forsett when they claimed the 31-year-old off waivers from the Detroit Lions. Because necessity demands it, Forsett is expected to be in uniform and available to play Sunday against the Tennessee Titans.
Forsett was the target that made sense for the Broncos because he’s played for Kubiak in two previous seasons -- 2012 in Houston and 2014 in Baltimore. In '14, when Kubiak was the Ravens' offensive coordinator, Forsett ran for a career-best 1,266 yards to go with 44 receptions for 263 yards.
It means Forsett largely knows the terminology in the Broncos' playbook. If his conditioning is in order -- and it should be given he was practicing with the Lions until this past week -- he should be the third back the Broncos will have in uniform to go with Booker and Thompson.
The Broncos will need Forsett to contribute in some way as they continue to struggle with that part of the offense. Anderson has the team's only 100-yard rushing game, which came on the night he was injured against the Houston Texans -- 107 yards in a game the Broncos rushed for 190 yards.
In the five games since Anderson's injury Booker has averaged just 2.8 yards per carry, including 1.9 yards per carry against the Jaguars -- 35 yards on 18 carries.
"It was below average," Booker said. " ... We just have to get better."
It might say a little something about the way things have gone that the Broncos' longest runs this season are both for 28 yards -- from Anderson and fullback Andy Janovich -- and both were in the season opener on Sept. 8. Bibbs' 24-yard run Sunday was the Broncos' only rushing attempt of over 19 yards since.
Anderson, Bibbs and Janovich are all now on injured reserve. So whatever happens in the run game from here on out will have to come largely from Booker -- who must clear the rookie wall and break a string of five consecutive games of 3.3 or fewer yards per carry -- and Forsett.
"There's no question we have to be better," Kubiak has said. "Our offense is more productive when we have some consistency in the run game."
