The Kansas City Chiefs were such a mess in their season opener against the Tennessee Titans that they were quickly written off, their dramatic turnaround last season considered a fluke.

Turns out that conclusion was premature.

After steadily improving over the first few weeks of the season, the Chiefs earned a marquee victory Sunday when they rallied for a 23-20 victory in San Diego — not only knocking off one of the NFL's hottest teams but taking a big step toward the top of the division.

Sure, the Denver Broncos remain the team to beat in the AFC West, and the Chiefs are still looking up the standings at the Chargers. But there is suddenly a feeling that the Chiefs can make some noise in the wild-card race, if not for the division title.

"I think overall the whole picture is good," Chiefs coach Andy Reid said Monday. "Yeah, it came down to the last drive, but there were a lot of people on both sides of the ball and special teams that put you in a position to be able to do that."

The Chiefs had chances to steal wins in Denver and San Francisco, but struggled in crunch time. They had no such trouble against the Chargers, marching 62 yards in nine plays in the waning minutes to set up a 48-yard, go-ahead field goal by rookie Cairo Santos.

The kick was a little bit wobbly. It looked a little bit funky. But it just managed to skirt inside the upright, helping to end the Chargers' five-game winning streak.

"I have 100 percent confidence in Santos," Chiefs tight end Travis Kelce said. "He has shown he can do it. In practice he barely misses. It's about confidence."

Santos might be indicative of the Chiefs' growing confidence.

After wrestling the job away from veteran Ryan Succop in training camp, Santos promptly missed field goals in each of his first two games. He hasn't missed since, including all three attempts against San Diego.

"That's the game of football," quarterback Alex Smith said. "You have to trust the guy next to you. We talk about it all the time — offensively, defensively, the guy next to you in the huddle — you have to trust all those guys to do their job. And you have to trust that you're going to do yours. It's no different with Cairo. The guy went out there and hit a great kick and had a great kickoff right after, so I'm happy for him."

Now, a resilient bunch of Chiefs that withstood a series of devastating injuries during the first couple weeks of the season has a relatively weak schedule ahead.

First up Sunday is a visit from St. Louis, coming off an emotional high from its victory over Seattle. Then comes a home game against the New York Jets, a team that has lost six straight games.

"The great part about this is there were a lot of people we could stand up here and mention. The great part about this is we still have a ton of room to improve," Reid said. "We've got a heck of a football team coming in here this week. Jeff (Coach Fisher) has done a nice job with the Rams. They are playing at a very high level, they're fast, they're aggressive. We've got to make sure that we get ourselves ready."