ENGLEWOOD, Colo. -- When James Casey’s knees didn’t cooperate and the Denver Broncos needed a roster spot to bring defensive end Derek Wolfe back from a suspension last season, the idea of having a fullback on offense was essentially placed in cold storage.

Call it gone, but not forgotten, the moment Casey was released and Wolfe re-joined the team. However, since the new football year started, coach Gary Kubiak is ready to bring the fullback option back. The next step is to try to find somebody for the position.

“There will be some on the roster, hopefully we have a couple going into camp, and we can get back to some of those two-back things,’’ Kubiak said. “Those guys are hard to come by; they really are. I think in the draft this year there are a few guys. I’m excited about that. We’d like to have one of those guys be a part of our roster.’’

When the Broncos, and quarterback Peyton Manning, sputtered out of the gate in 2015 in the new offense, the two-back set was largely an ornamental affair with just three snaps in the season-opener against the Baltimore Ravens, five snaps in the Week 2 win over the Kansas City Chiefs, four snaps in Week 3 and four more in Week 4.

Then Wolfe returned from a four-game suspension for violating the league’s policy on performance-enhancing drugs, and Casey was released to make room on the roster. With those moves, the two-back set was gone as well.

Over the next eight games, the Broncos were in a two-back set for two snaps total -- one against the Cleveland Browns and one against the San Diego Chargers.

In the final four games of the season, the Broncos were in a two-back set for four snaps on Dec. 13 against the Oakland Raiders and three snaps against the Cincinnati Bengals. In all, that was 25 plays for the season, often with backup center James Ferentz lined up as the lead back. Kubiak is looking to increase that number as the Broncos try to pump up the run game overall.

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“Obviously the thing with James didn’t work out,’’ Kubiak said. “He tried to battle through some knee stuff. In Week 3 or 4, we went in a different direction and became a one-back football team. We’ll see, but I’d like to have one.’’

Also, as part of the running back makeover, Kubiak said he has told Kapri Bibbs, who spent most of the 2015 season on the team’s practice squad but rushed for 1,741 yards as a sophomore at Colorado State, that he needs to do to get on the field as a runner.

“He hasn’t done anything in this league so it’s time to go do something,’’ Kubiak said. “That means he’s going to have to take a big step as a player, as a special teams player; he’s got to work himself into that. He shows flashes of 'I can do this', but it needs to be on a consistent basis, and he and I have had that talk. The talent is there … it’s going to be up to him.’’

Kubiak also didn’t rule out a return of Ronnie Hillman. Hillman, an unrestricted free agent, remains unsigned. But after the Broncos matched a four-year, $18 million offer sheet to C.J. Anderson, Hillman is likely still searching for more carries and a bigger contract than the Broncos could offer.

But Kubiak said this week that “Ronnie did a good job for us … we’d love to have him back.’’

Hillman, a third-round pick by the Broncos in 2012, was the Broncos’ leading rusher this past season with 863 yards and seven touchdowns. He had four 100-yard games in 2015.