Raiders fall 30-27 to Chiefs as Kenneth Walker runs for 177 yards

The Raiders' undefeated start is over, and the bill came due inside 20 seconds of fourth-quarter football. Kansas City won 30-27 at Allegiant Stadium on Sunday night to move to 4-0 and take the AFC West lead. Las Vegas falls to 3-1 with a trip to New England next.

Kenneth Walker III did most of the damage. He ran for 177 yards and two touchdowns on 22 carries, including a 76-yard burst late in the third quarter, per the team's own recap. Patrick Mahomes threw for only 225 yards and did not need more, because the Raiders never made him carry the offense.

Two plays settled it. With Las Vegas ahead late, Mahomes found Tyquan Thornton for 55 yards on third down and Walker scored from two yards out with 3:21 left, as KTNV reported. On the ensuing kickoff, Chiefs linebacker Jeffrey Bassa punched the ball loose from Dareke Young, and Walker went 22 yards for the touchdown that turned a one-score game into a two-score hole.

Kirk Cousins answered with a 20-yard touchdown to Brock Bowers and finished with 365 yards and two scores, though 52 attempts tells you what the run game offered: 72 yards at 2.8 a carry, by ProFootballTalk's accounting. The last drive died at Xavier Nwankpa's interception near midfield. "That's one of the plays I'll be driving home thinking about," Cousins said.

Klint Kubiak's third-quarter call will get re-litigated all week. An illegal formation penalty wiped out a field goal, and instead of taking the three he went for it on fourth and 2 in the red zone. The pass to Ashton Jeanty fell incomplete. "We were going to be aggressive going into the game. I don't regret it. I regret not getting it," Kubiak said. Opinion: he's right on the principle and wrong on the arithmetic. Three points you declined, in a three-point loss, is not a rounding error.

The injury ledger is mixed. Jalen Nailor left late in the second quarter with a concussion and did not return. Jeanty, who has been managing an ankle since before the season, posted 126 scrimmage yards and told reporters he feels he will be "100 percent real soon." Thornton got the worst of it: NFL Network's Ian Rapoport reported the Chiefs receiver dislocated his ankle and is out indefinitely.

Watch Nailor's path through concussion protocol and whether Jeanty's ankle shows up on Wednesday's practice report. The bigger line item is a run defense that just handed one back 177 yards. New England on the road is no place to keep testing it.