Gannon's scores helped lift the Raiders into a four-point halftime lead. But the All-Pro quarterback was stripped by defensive end Duane Clemons with two minutes left in the game and safety Greg Wesley recovered at the Oakland 28.
Chiefs tight end Tony Gonzalez caught a 24-yard touchdown pass from Trent Green to close the Kansas City deficit to 28-26. But Green was sacked on the two-point conversion attempt and the ensuing onside kick failed as the Raiders (9-3) secured their position atop the AFC West.
"We did not play our best brand of football in any phase," Raiders coach Jon Gruden said. "But I was very pleased, obviously, with our team finding a way to win."
Oakland returner David Dunn muffed a punt last Sunday in overtime and Arizona rookie LeVar Woods recovered at the Raiders' 25, helping set up a field goal as the Raiders suffered a surprising 34-31 loss. Dunn was released earlier in the week.
Brown became the 13th player in NFL history with 100 touchdowns. He also caught four passes against the Chiefs (3-9), who he has victimized for 1,754 receiving yards -- his highest total against any opponent.
"It's special to me," Brown said. "There's not too many guys in this league who can get 100 scores. We have a short week this week, so I can't think about it too long. But at the same time, it is a good feeling."
"I'll say this about Tim Brown as a punt returner, it's one of the reasons I like Notre Dame so much," Raiders coach Jon Gruden joked, referring to press reports connecting him to the no-longer vacant coaching position at Brown's alma mater.
It also proved to be a historic afternoon for the Raiders' other star wideout. Jerry Rice made a nine-yard reception, his second of the game, with 7:09 remaining in the first half. The 17-year veteran became the first NFL receiver to compile 20,000 career yards.
"What a way to get your 100th touchdown in pro football, unbelievable. For Jerry Rice to go over 20,000 yards in the same game. I don't know, we'll have our parade in Ruby Hill, back where I live," Gruden said.
Oddly, the most prolific wide receiver in NFL history fumbled on the play, forcing him to recover the ball at the Oakland 18.
"I couldn't think of a better place to do it then right here at home in Oakland," Rice said. "I'm very happy about it. Today was a day where we had some bad things and we had some good things. So, I was happy to see Tim catch his 100th touchdown."
Priest Holmes had 22 carries for 168 yards, becoming the first Kansas City running back to gain 1,000 yards in a season since Christian Okoye accomplished the feat in 1991. He also caught five passes for 109 yards.
The AFC West rivals also engaged in one of the NFL's best games this season in Week 1, with the Raiders posting a 27-24 victory on Sebastian Janikowski's 31-yard field goal with 15 seconds remaining.
"The Raiders are on the way to win a division championship," Chiefs coach Dick Vermeil said. "We moved up a notch in the ability with which we played and I just think you'll see the Chiefs growing."
The Raiders have pulled out three straight victories over the Chiefs with a late field goal at Arrowhead Stadium.
In a series known for its dramatic finishes, Sunday's edition commenced with 5:46 left and Kansas City trailing by eight.
Green's pass intended for Eddie Kennison was intercepted by linebacker Travian Smith. The Raiders' linebacker returned it nine yards before Kennison re-appeared to strip his opponent.
Running back Tony Richardson covered up at the Oakland 39, giving Kansas City a new set of downs.
The Chiefs immediately went back to the running game, which the Raiders defense has had trouble with in recent weeks. Beginning with its Nov. 11 contest at Seattle, where it yielded 266 yards to Shaun Alexander, Oakland had allowed 769 net rushing yards over a stretch of four games.
"We will critique every aspect of our football team," Gruden said. "We've got to do a much better job of tackling and if we don't, it's going to be difficult to stop anybody's running game."
Holmes had a 16-yard run and Richardson carried twice for 14, setting up Kansas City's first and goal on the Oakland nine.
A former Baltimore Raven, Holmes worked his way to the four on two carries. But when the Chiefs returned to the air, Green threw an incompletion and was foiled on fourth down by a diving effort from cornerback Charles Woodson.
"If we're a championship team, we have got to be our best in the playoffs," said Woodson, whose team remained one game behind Pittsburgh in the race for the AFC's best record. "We're good, but we have to be a lot better to get to the Super Bowl."
Having used its final timeout in between passing attempts, Kansas City turned the ball over on downs at the five with Oakland looking to run out the remaining 2:59.
Running back Charlie Garner got the clock down to the two-minute warning with a pair of short gains.
Needing to convert on third and five and slide safely to secure the victory, Gannon ran around left end and picked up seven yards, but did not anticipate the swiping arm of Clemons.
Kansas City had 1:49 with which the work, but only needed 11 seconds to get into the end zone. After hitting Richardson with a three-yard sideline pass, Green went straight for the reliable Gonzalez for a 24-yard touchdown strike.
But Green did not appear nearly as decisive on the two-point conversion attempt. He pump faked and searched the end zone for a target, giving the defensive line enough time to reach him.
"We missed a lot of opportunities. I think as well as we did in all phases, we had plays I wish we had back," Green said. "They stripped the ball from Gannon after the first down. Offensively, we never gave up. We keep on going right until the end when we scored."
Peterson, who missed a 28-yard field goal earlier, sent the onside kick 14 yards upfield. But Raiders receiver Jerry Porter gathered it in, allowing Gannon a second chance to drop to his knee three times and let the clock expire.