OAKLAND, CALIF. ? The Oakland Raiders gave Kansas City’s defense a serious confidence boost two months ago, and the Chiefs needed it badly.

The league’s last-place defense held the NFL’s top-rated offense to its lowest point total of the year in a 20-10 win at Arrowhead Stadium on Oct. 27. And the Chiefs don’t hesitate to let people know about it.

They believe there’s no reason they can’t do it again today, but they realize it will be a lot tougher with the rowdy Raider Nation going against them on every down.

This game also carries more importance for both teams. The Raiders (10-5), who won the AFC West for the third straight time, could secure home-field advantage through the playoffs, and the first-round bye that accompanies it, with a victory. The Chiefs (8-7) still can make the playoffs, which would snap a four-year postseason drought.

Raiders quarterback Rich Gannon put up big numbers in that loss to the Chiefs two months ago, completing 35 of 55 passes for 334 yards, but he couldn’t get his team into the end zone often enough. It was the third defeat in Oakland’s four-game losing streak.

“I think we got after them pretty good up front,” said Chiefs linebacker Mike Maslowski, who needs six tackles to break the franchise single-season record of 157 set by Gary Spani in 1979.

“We put some good pressure on Gannon and made him make some quick decisions, didn’t let him sit back and scan the field and choose who he wanted to go to. We played hard, we played physical. It was pretty evenly matched, and we got the best of it at the end.”

That same defense had blown double-digit fourth-quarter leads in bitter losses the two previous weeks. Against the Raiders, however, the defense set up the clinching touchdown when Maslowski forced a fumble by Jerry Rice and recovered the ball with 4:39 left.

The win was the first for the Chiefs over the Raiders in six games.

Stopping Gannon this time will be just as difficult. He set an NFL record last week against the Broncos for the most completions in a season with 411, and if he has a spectacular passing game today, he could put another prestigious record next to his name. He needs 390 yards to become the second quarterback to pass for 5,000 in a season. Dan Marino had 5,084 in 1984.

“Their front seven is playing very well right now and they’re a very aggressive group, with a lot of team speed up front,” the 37-year-old Gannon said. “They’re very solid. We’ve just got our work cut out for us.”

Gannon hasn’t lost any faith in Oakland’s creative and gutsy offensive system, despite low numbers the past two weeks.

“It’s a system that’s been very productive for us,” he said. “However, if you make mistakes or make mental errors and you’re not clean in your performance, then it’s tough.”

The Raiders implemented more rushing plays to beat Denver last week. During one series, they ran the ball six straight times.

“Now they create more problems for you,” Chiefs coach Dick Vermeil said. “Gannon just runs that whole group so well. He controls the pulse rate of the offense, if not the entire football team.

“He’s a competitive guy who takes advantage of all his talent and hasn’t made many mistakes this year. Very few. He’s the magician that makes it all work.”

The Chiefs wish they had already secured a playoff spot, but they also believe playing in such a big game in the season’s final weekend will be exciting.

“They’re playing for a lot, and so are we,” Maslowski said. “It will be another really tough game. It would be nice to have it be unmeaningful in the sense that we were going into the playoffs already. But to have this opportunity, this is the first time since I’ve been here where there’s been a lot of meaning in the last game.”