It's not unusual for 40-year-old Matt Hasselbeck to have doubters about his ability to hold down the Colts starting quarterback spot for as many as six weeks while Andrew Luck recovers from kidney and abdominal injuries.

It is unusual for one of Hasselbeck's doubters to be his brother Tim.

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Tim Hasselbeck, an ESPN analyst, said Wednesday on the World Wide Leader that he is not optimistic about his brother holding up that long, Pro Football Talk reported.

"They have a 40-year-old backup that maybe has to play for six weeks, get you all the way to Week 16 of the NFL season before you potentially get Andrew Luck back," Hasselbeck said. "I know my brother played well in the two games he started this season, but I think anyone can attest ... it's one thing when it's a shorter injury and you have a backup that's going to play one week, two weeks, three weeks maybe. We're in a situation where they have a 40-year-old quarterback that's potentially going to play half of their football games this year. Half of them!"

Pro Football Talk reeled off names of multiple quarterbacks that had success in their 40s, including Brett Favre, Doug Flutie, Warren Moon and Vinnie Testaverde.

"But Tim Hasselbeck is right that those players are the exception, rather than the rule," PFT added.

Matt Hasselbeck led Indianapolis to victories in Weeks 4 and 5, and the Colts are currently leading the AFC South with a 4-5 record. They have a half-game lead over the Texans, who are 3-5, so it's not as if Hasselbeck has to play lights-out during Luck's absence.

Indianapolis has a bye this week before traveling to play at Atlanta in Week 11. They're reportedly trying to lure Jason Campbell out of retirement to serve as Hasselbeck's backup until Luck returns, but indications are that he won't return, according to SI.com.

Tim Hasselbeck believes Indy better have a backup plan -- sooner rather than later.

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