Andrew Luck
Andrew Luck is 15-6 in his 21 regular season games. Reuters

In his rookie season, Andrew Luck led the Indianapolis Colts to a nine-game improvement and a trip to the playoffs. This year, the quarterback could be ready to take the next step in his NFL career.

The Colts enter Week Six with a 4-1 record and as one of the favorites in the AFC. Only the Denver Broncos and New England Patriots have a better chance to reach the Super Bowl, according to the Las Vegas Hotel & Casino. Those odds could improve after their Monday night contest with the San Diego Chargers.

The Colts close out the week with a trip to the West Coast. They face a 2-3 Chargers team after picking up a few impressive wins. In Week Three, the Colts pulled off one of the biggest upsets of the season, defeating the 49ers in San Francisco. Last week, they gave the Seattle Seahawks their first loss of 2013. Despite their hot start, the Colts are aware of the challenges that lie ahead.

"I don't think you'll see any of these guys walk around with their chest puffed out like a robin, walking around the yard after a big rain storm, bunch of worms out there, all robin-ed up," head coach Chuck Pagano said. "We're not going there. We'll keep reminding them it's a short ride from the penthouse to the outhouse."

Luck's maturation has been on full display in 2013, throwing just two interceptions and ranking in the top 10 in passer rating. His decision-making has improved significantly from a year ago, and has thrown with more accuracy, elevating his completion percentage from 54.1 to 62.2 percent.

The quarterback doesn’t have much experience playing in primetime. His visit to San Diego will be his first appearance on Monday Night Football.

“Preparation shouldn’t change,” Luck said. “Yes, it’s a day later. We had this extra day [on Wednesday]. Flying to the West Coast, I’m glad we were able to do that with San Francisco to figure that out. You don‘t want to take away from it being Monday night. You prepare the same, and you know it’s a good San Diego team.”

While Luck has increased his level of play from a year ago, so has the Chargers' quarterback. Philip Rivers has returned to the form that made him one of the league’s top signal callers at the end of the last decade. His improved performance, though, hasn’t translated into wins. The Chargers are tied for last place in the division and will hold sole possession of it if they can’t hold off the Colts.

Rivers’s passer rating and completing percentage are good for second in the NFL, with only Peyton Manning having better numbers. He is, however, coming off his worst game of the season. The Chargers were upset in Week Five by the Oakland Raiders after three interceptions by the veteran quarterback.

Rivers should have his top running back available on Monday night. Ryan Matthews suffered a concussion last week, but is listed as probable. He, along with Danny Woodhead and Ronnie Brown, could get a lot of carries against the 30th ranked rushing defense. The Indianapolis defense, though, has been able to limit their opponents’ points by forcing 10 turnovers.

"They play great team defense," Brown said. "They always have that bend-but-don't-break mentality, so on offense we have to go in and not give them any extra possessions. We have to make sure to hold onto the ball and take care of our fundamentals."

Kickoff Time: 8:30 p.m. ET

Points Spread: Indianapolis -2

Over/Under: 50

TV Channel: ESPN

Live Stream Details: WatchESPN

Prediction: Indianapolis 27, San Diego 24

National Football League