Adam Schefter explains why Matt Hasselbeck will start at quarterback for the Colts instead of Andrew Luck. (0:45)

Matt Hasselbeck will start at quarterback for the Indianapolis Colts on Thursday night when they visit the Houston Texans.

Colts coach Chuck Pagano had said his team would "do the right thing" regarding Andrew Luck and his injured shoulder. The Colts have not described the exact nature of Luck's injury but have said there is "zero truth" to reports that Luck has a partial shoulder subluxation.

Luck, who missed his first NFL game last weekend, is inactive for Thursday night's game. Quarterback Josh Johnson, who re-signed with the Colts on Wednesday, will serve as Hasselbeck's backup.

Luck threw lightly at practice Tuesday, and despite his optimism, the team had been unsure if he would be able to play against Houston. He was listed as "limited" in Tuesday's practice, according to Pagano.

Hasselbeck has his own issues. He has been dealing with a virus this week that has limited his practice time, a Colts official told ESPN on Thursday.

The Colts' Matt Hasselbeck will start at quarterback for the second straight game in place of the injured Andrew Luck. AP Photo/R Brent Smith

Hasselbeck was in an emergency room until 2 a.m. Tuesday dealing with the virus, which is still affecting him, and he did not throw a pass in practice this week.

He started in Luck's place Sunday and led the Colts to a 16-13 overtime victory over the Jaguars. He was 30-of-47 for 282 yards and a touchdown.

It was the first game this season the Colts had not thrown an interception, and the 282 yards passing are a season high. Luck, in his three starts this season, has thrown five touchdown passes but has seven interceptions.

With his start against the Jaguars, Hasselbeck, 40, became the oldest quarterback to start an NFL game since Brett Favre in 2010, according to ESPN Stats & Information. Favre was 41 when he made his start.

ESPN Colts reporter Mike Wells contributed to this report.