Jamaal Charles did not play in the Broncos’ preseason opener at Chicago on Thursday. And it is unclear if the veteran running back will suit up Saturday at San Francisco.

“I’m not sure yet,” coach Vance Joseph said when asked if Charles would play against the 49ers.

Charles, signed to a one-year contract by the Broncos in the offseason after spending his first nine seasons with AFC West rival Kansas City, remains one of Denver’s biggest question marks as the team enters its final month of preparations before the Sept. 11 regular-season opener against the Los Angeles Chargers.

Though his full-team repetitions have been elevated during the past week, Charles has still seen limited action as he continues to recover from multiple knee surgeries the last two years.

The man who has rushed for at least 1,000 yards in a season five times insists he is not feeling pressure as roster decisions creep closer.

“I don’t think I have to prove anything,” he said. “… People know what I can do. I feel confident. Whatever Coach Vance (Joseph) and the trainers say, that’s their direction. I’m just out here every day just getting healthy and getting my craft ready and preparing to play whenever.”

Joseph said the Broncos will “probably” need to see Charles, whose one-year deal could reach $3.75 million with incentives, play in the preseason before making a roster decision with the running back. Related Articles September 20, 2020 Broncos, led by backup quarterback Jeff Driskel, see comeback fall short in loss to Pittsburgh

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“He’ll eventually play,” Joseph said. “It depends on the (doctors) and how he’s feeling.”

Charles said he has experienced no setbacks as he’s gradually participated more in practice this month. He has made a concerted effort, he said, to run on his right side and cut off the knee that has been wrapped in a brace and was operated on as recently as November.

“I’m out here,” he said. “Whenever they throw me in the fire, I’m going to be ready.”