The Chiefs used a long, time-consuming drive to take a 10-7 lead on the Bills.
Then Buffalo came right back and needed only five plays to regain the advantage.
Quarterback Josh Allen threw his first touchdown of the night, hitting receiver Emmanuel Sanders in the end zone for a 35-yard touchdown to give Buffalo a 14-10 lead.
That came after Allen kept the possession alive on third-and-2 with an 8-yard pass to receiver Stefon Diggs — his first catch of the night. And then Allen hit running back Zack Moss for a short pass that he took 24 yards.
Sanders now has three touchdown receptions for Buffalo this season.
And Kansas City’s defensive woes continue, as the unit has surrendered four plays of at least 20 yards in the first half.