Count former Colts GM Bill Polian among those who believe Indianapolis has a legitimate shot at winning the Super Bowl this season.

"It all starts with Andrew (Luck) and clearly he's the best of the young quarterbacks that have come into the league in terms of everything he can do and he has a chance to be one of the greats before it's all said and done," Polian said, via ESPN's Mike Wells. "They're extremely fortunate to have him. And when you do, you're automatically a contender when you have a quarterback of that magnitude."

Beyond the presence of a franchise quarterback in Luck, Polian pointed to the offseason additions of running back Frank Gore and wide receiver Andre Johnson as significant upgrades, but cautioned the window to win a championship with the team's current roster is narrow.

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"Those are terrific additions, but they're obviously not long-term additions," Polian said. "The question is: Even if they can reach the heights this year, which they're certainly capable of doing if they play good defense, how do you sustain it? But this year, they're as good as anybody, that's for sure."

Polian, the architect of the Colts' Super Bowl XLI-winning team, said the fate of this season likely rests on improvement from the defense. Indianapolis has allowed the New England Patriots to rush for a combined 657 yards in the past three meetings between the two teams.

"Can they play adequate enough defense to be able to really be a challenger? Obviously what we saw last year in the (AFC) championship game is not good enough and they were soundly beaten by the Patriots twice," Polian said. "So that's a hurdle they're going to have to overcome, but it's going to have to be on defense."

(h/t ESPN)

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