Chiefs start undrafted rookie Kahlil Benson at left tackle with Josh Simmons out in opener vs Denver

KANSAS CITY, Mo. (AP) — The Kansas City Chiefs were missing left tackle Josh Simmons to protect quarterback Patrick Mahomes when they faced the NFL's top pass rush from last year in their Monday night opener against the Denver Broncos.

Simmons, a first-round pick a year ago, has been out since mid-August with a back injury, leaving the Chiefs in the unenviable position of starting undrafted rookie Kahlil Benson at left tackle. Benson was signed after an impressive showing at a rookie minicamp, and he climbed through the depth chart so quickly that he likely would have started against Denver at right tackle anyway.

“Go play and have fun. That's all you can say,” Chiefs offensive coordinator Eric Bieniemy said this week. "Yes, he is a young player. He’s going to have some good plays, he’s going to have some bad plays. But when it’s all said and done with, he just needs to go out there and play and have fun.”

With Benson moving to left tackle, the Chiefs inserted veteran Jaylon Moore at right tackle.

The Chiefs also were missing safety Chamarri Conner from their rebuilt secondary because of a knee injury, though three-time All-Pro defensive tackle Chris Jones was available after showing up on the injury this week with a calf issue.

The Broncos were playing without linebacker Jonathon Cooper, who pleaded not guilty last month to multiple charges stemming from altercations with his then-girlfriend in June. He remains on the commissioner's exempt list with a trial scheduled for November.

Denver promoted long snapper Mitchell Fraboni and fullback Adam Prentice from the practice squad for the game. Fabroni has played in 55 regular-season games and three postseason contests, while Prentice made three starts and appeared in 17 games last season.

Broncos running back Tyler Badie, offensive lineman Kage Casey, tight end Dallen Bentley, defensive end Jordan Jackson and defensive lineman Tyler Onyedim were inactive. Wide receiver Lil’Jordan Humphrey was released earlier in the day.

The Chiefs activated defensive tackle Marcus Harris and fullback Ben VanSumeren from the practice squad for the game. Along with Simmons and Conner, they made inactive quarterback Garrett Nussmeier, wide receiver Jared Wiley, offensive lineman Diego Pounds, linebacker Jack Pyburn and defensive tackle Bryson Eason.

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