KANSAS CITY, Mo. — Running back Kenneth Walker III stole the show in his Kansas City debut as the Chiefs dominated the Denver Broncos 31-10 on Monday night at Arrowhead Stadium.Walker, who signed with the Chiefs after winning the Super Bowl MVP with the Seattle Seahawks in February, rushed for 173 yards on 23 carries and scored two touchdowns.Walker made it easy for quarterback Patrick Mahomes, who played his first game since knee surgery in December. Mahomes proved early that his knee was sound, rushing four times for 27 yards and a touchdown. He finished 15 of 27 passing for 184 yards and two touchdowns.It was a bad night all around for the defending AFC West champion Broncos, who were outgained 392-177 in total yards, including 220-62 on the ground. Quarterback Bo Nix was only 17 for 28 for 131 yards and had two turnovers.What does Walker’s monster Chiefs debut mean for the offense and its aspirations this season?One of the biggest criticisms of the Chiefs offense last season was that the team didn’t do enough to help Mahomes.That led to an offseason in which — mostly — all the team did to upgrade offensively was bring in Walker as an expensive free agent.Through one week, it looks like a genius move. If Walker stays healthy, he could be enough to completely change what this offense looks like.The Chiefs made Walker their three-down workhorse back Monday, and he delivered in nearly every way imaginable. He broke two 20-plus-yard runs; Chiefs running backs had just one all of last season.Kenneth Walker III and Patrick Mahomes celebrate after a touchdown on Monday night. (Jamie Squire / Getty Images)He was effective in the pass game. He was good in short yardage and also broke nine tackles in the first half alone, per NFL’s Next Gen Stats.But perhaps more than anything else, Walker allowed the Chiefs to establish a physical mentality, with the offensive line getting downhill to take over the game from the early stages.“It’s a mentality and it’s an attitude,” Mahomes said of what Walker brings to the Chiefs. “He sets the tone. We talked about it all week long: against this defense, you’ve got to set the tone. This offensive line and those running backs did that.”Add all that to what we’ve seen Mahomes do previously? Yes, Walker has to stay healthy, but it’s difficult not to dream of an entirely different Chiefs offense being unlocked thanks to his presence. — Jesse NewellBroncos’ splashy new addition a non-factorAs Jaylen Waddle slammed the brakes on a comeback route during Denver’s second drive, three Chiefs defenders shaded in his direction, determined not to let the Broncos’ dangerous new receiver cause damage after the catch. That attention let tight end Evan Engram come open across the front of the end zone and Nix hit him for a 19-yard touchdown pass that tied the game.