The Chiefs made the AFC West a three-team race on Sunday by beating the Chargers 23-20 on rookie Cairo Santos' 48-yard field goal with 21 seconds left, snapping San Diego's five-game winning streak.
''I think this team is in a good place mentally,'' Smith said. ''We took this challenge on, and we had two weeks to get ready with the bye week. We took it on as a challenge with no one giving us a chance. We felt like coming into this game, we were a couple plays away from being 4-1.
''This was an opportunity for us to kind of show what we're made of, show the country. I feel like we're in a good place and we'll keep going.''
The Chiefs improved to 3-3. San Diego (5-2) dropped into second place behind Denver (5-1), which beat San Francisco 42-17 on a record-setting night by Manning.
Here are some things that stood out Sunday as the Chiefs surprised the Chargers:
ALEX AT THE Q: Smith knows Qualcomm Stadium well, from teaming with Reggie Bush to lead Helix High to consecutive San Diego Section championships to throwing five touchdown passes against San Diego State for Utah in its BCS-busting season of 2004.
Smith earned his first NFL victory at the aging concrete bowl in Mission Valley on Sunday.
''There might be something to it. I'm definitely comfortable here,'' Smith said. ''I've played a lot here - high school, college and as a professional. I think it had more to do with executing out there for sure.''
That, he did. Smith completed three straight passes for 43 yards on the drive capped Santos's winning field goal.
Smith completed 19 of 28 passes for 221 yards and one touchdown.
ANDY'S DANDY: Coach Andy Reid, in his second season with the Chiefs, improved his career record in games following a bye week to 14-2 (.875), the most victories of any NFL head coach in games following a bye week.
''I don't think there's a secret to it,'' said Reid, who compiled most of that post-bye magic while coaching Philadelphia. ''When we have good players and good coaches, good things happen. I've been lucky enough to be in those situations.''
RUSHING RECORD: Jamaal Charles scored once and gained 95 yards to give him 6,113 for his career, moving him to the top of Kansas City's career list. He passed Priest Holmes, who had 6,070.
Charles was more impressed with the win.
''That was my first time winning here,'' Charles said. ''That was big, it was a big win. That's a good team, they have a great defense, great quarterback on their side. That was an amazing game to pull off today. The team fought with will, and we went out there to play a great game.''
Charles weaved in and out of traffic to score on a 16-yard run on the first play of the second quarter. Former teammate Brandon Flowers leveled him a yard into the end zone, too late to keep the Chiefs from tying it at 7.
Flowers later left the game with a concussion.
''Flowers put a big hit on me, but I'm thankful that I got up healthy,'' Charles said.
PERSPECTIVE CALLING: ''When you win five in a row, losing stinks,'' San Diego's Philip Rivers said. ''We have to handle it right and get ready to go to Denver on Thursday night and not let this thing go to two in a row.''
Rivers was 17 of 31 for 205 yards and two touchdowns. After setting an NFL record with five straight games with a passer rating of 120 or better, he tumbled to 83.4.
Antonio Gates caught a 27-yard touchdown pass from Rivers just before halftime. It was the 67th career TD pass from Rivers to Gates, the most in NFL history from a quarterback to a tight end.
NICK THE KICKER: San Diego's Nick Novak kicked a 48-yarder to tie the game with 1:57 left.
Novak has 31 straight field goal conversions, breaking John Carney's team record of 29 set in 1992-93.
Earlier, he kicked a 24-yarder to pull the Chargers to 20-17.
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