A pair of third-quarter touchdowns helped the Chiefs (7-4) past AFC West rivals the Chargers (4-7) at the Estadio Azteca.
Chiefs star Patrick Mahomes improved in the second half and finished with 182 yards on the back of 19 of 32 completed passes with one TD and an interception.
Travis Kelce led the Chiefs with 92 receiving yards, including a TD, in a key win for division leaders Kansas City, who had Tyreek Hill suffer a hamstring injury.
Kelce became the fastest tight end in NFL history to reach 6,000 yards and 450 receptions, according to the Chiefs.
Philip Rivers (28 of 52 for 353 yards with one TD) almost saw the Chargers to a late victory, but the QB threw his fourth interception in the dying seconds.
After a first-quarter Michael Badgley field goal for the Chargers, the Chiefs took a 7-3 lead when Tyrann Mathieu intercepted Rivers, allowing LeSean McCoy to rush across from six yards for a TD.
Badgley made two more field goals – either side of one from Harrison Butker – as the Chiefs took a 10-9 lead into half-time.
Mahomes was better in the second half as the Chiefs scored twice to go ahead 24-9.
Darrel Williams rushed over before Mahomes' 23-yard pass for Kelce saw the Chiefs take control.
However, the Chargers responded when Rivers found Keenan Allen and a two-point conversion brought them back within seven.
Rivers looked to lead the Chargers on a scoring drive late and a 50-yard pass to Mike Williams set up a potential TD, but the QB was intercepted again in the closing seconds.