CENTENNIAL, Colo. -- Justin Forsett requires no microwave study session.
He knows coach Gary Kubiak's offense from time spent together in Houston and during a career year in 2014 in Baltimore. Forsett arrived Wednesday ready to play a significant role. He will serve as slumping rookie Devontae Booker's backup, filling the spot vacated by the injured Kapri Bibbs.
"I got a lot reps in this system way back in Seattle with (quarterback coach) Greg Knapp and (line coach) Alex Gibbs. Then with Kubiak. I am comfortable in this offense," said Forsett, who will wear No. 20. "I don't know what my role will be but I am here to contribute. I hope to provide a spark."
Forsett brings fresh legs. He saw limited duty with the Ravens and Lions this season, rushing 44 times for 136 yards. Forsett posted a season-high 14 carries in week two with Baltimore. The idea of him posting 10 carries this week is conceivable with the Broncos prepared to play the hot hand.
"He understands exactly what we're doing," Kubiak said. "He can help us really quick."
Added offensive coordinator Rick Dennison, "He's always been productive. He's always been sharp on all of his assignments. I think he will be ready."
The Broncos rushed for 104 yards at Jacksonville, fueled by Bibbs. His season ended when he landed on the injured reserve with a sprained left ankle.
Marshall sits out
The likelihood of linebacker Brandon Marshall playing continues to decrease because of his problematic left hamstring. He told Denver7 he feels "OK." But he did not participate Wednesday. If Marshall can't go, Corey Nelson would start in his place. Nelson continues to receive a few more plays each week by design.
Broncos safeties Darian Stewart and T.J. Ward could play a pivotal role in slowing the Titans' running game. Ward is comfortable in the box, and Stewart hits as hard as anybody on the team. "We have to put on the big boys pads. It's going to be physical," Stewart said.
... Will the Broncos pass more whether Paxton Lynch or Trevor Siemian starts? Tennessee owns the 26th-ranked pass defense, allowing 270 yards per game. The Titans have shown they can stop the run, but their secondary remains vulnerable.
... After league review, outside linebacker Von Miller was credited for a sack and forced fumble for his fourth quarter damage against the Jacksonville Jaguars. Miller leads the NFL with 13.5 sacks.
... Broncos tight end Virgil Green was named the team's Walter Payton Man of the Year. "I have a passion for helping kids," Green said.