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Indianapolis Colts quarterback Andrew Luck is reportedly in serious danger of missing his team's Week 1 showdown against the Los Angeles Rams as he continues to recover from offseason shoulder surgery.

Appearing on SiriusXM Fantasy Sports Radio Thursday (via ESPN.com's Mike Clay), ESPN.com's Mike Wells said "the odds are against" Luck being in uniform for the Colts' season opener.

Wells' report comes two days after Colts head coach Chuck Pagano told reporters he still didn't have a timeline regarding Luck's return, according to the Indianapolis Star's Stephen Holder.

Colts owner Jim Irsay has also been elusive about when Luck will be back at full strength.

On Aug. 13, Irsay said Luck will "be ready around the start of the season," but he left things open-ended rather than offering an exact date, per the Indianapolis Star's Zak Keefer.

If Luck—who is still on the physically unable to perform list—isn't under center on Sept. 10, it will be up to journeyman Scott Tolzien to get the Colts off to a fast start.

In his lone start last season—a 28-7 loss to the Pittsburgh Steelers—Tolzien completed 22 of 36 passes for 205 yards, one touchdown and two interceptions.