Chiefs lead Chargers 13-12 after 3rd quarter
Novak, who missed from 52 yards late in the first half, connected from 44, 42 and 26 yards in a third quarter that was dominated by the Chargers defense.
The Chiefs went three-and-out on their first possession, quarterback Matt Cassel threw his second interception of the game on their next try, and they went three-and-out again after that.
Still, the Chiefs (3-3) held the most meager of leads in part because the Chargers were beating themselves. Phillip Rivers has thrown two interceptions, Ryan Matthews fumbled the ball away to spoil a promising drive, and San Diego (4-2) has been called for 11 penalties.
Left tackle Marcus McNeill has been whistled for three false starts and a holding call.
Kansas City, which has won three straight after an abysmal start, can move into a tie for first in the AFC West with San Diego and the idle Oakland Raiders with a victory before a raucous crowd of 72,733 on Halloween night. The Chiefs would be the first team in NFL history to lose their first three games and be tied or leading a division after seven games.
They had things going the right direction early.
Cassel hit Jonathan Baldwin for 17 yards to convert a long third down on the Chiefs' first drive, and Dwayne Bowe for 26 more on another third-and-long to set up Ryan Succop's 36-yard field goal.
Rivers threw his second interception of the quarter a few minutes later, turning the momentum back to the Chiefs. Cassel hit fullback Le'Ron McClain for 16 yards, and a personal foul penalty for hitting a defenseless receiver on San Diego moved the ball to the Chargers 39.
Cassel dropped back to pass and saw Baldwin streaking for the end zone. The rookie wide receiver out-jumped fellow rookie Marcus Gilchrist and hauled in his first career touchdown catch.
Rivers continued his early season struggles in the first quarter.
The three-time Pro Bowl quarterback was intercepted by Kendrick Lewis on the first play of San Diego's second possession. His second pick was tipped by defensive lineman Wallace Gilberry and dropped into the hands of Chiefs linebacker Derrick Johnson.
Succop kicked his second field goal of the game just before halftime for a 13-3 lead.