Laremy Tunsil is poised to undergo surgery on a thumb injury and is expected to miss around four weeks of action for the Houston Texans.

The Texans face the Indianapolis Colts in an AFC South battle on Sunday with both teams struggling on 1-4 records and trailing the division-leading Tennessee Titans (3-2).

Houston will look to get their season on track against the Colts without Tunsil, who suffered a torn UCL in his thumb during the 25-22 loss to the New England Patriots in Week 5. He had initially hoped to play through the injury.

Texans head coach David Culley confirmed the surgery for star left tackle Tunsil, who was a Pro Bowler in 2019 and 2020, with the team "not really sure" how accurate the four-week recovery timeline will prove to be.

He also reiterated Tyrod Taylor will be the team's starting quarterback when he returns from a hamstring injury, but rookie backup Davis Mills will again start in his stead against the Colts.

"[Taylor] gives us the best chance to win," Culley said, per ESPN. 

"He's our starting quarterback. He was our starting quarterback when he went down. He was doing an excellent job. When he comes back, he'll still be our starting quarterback."

The Colts, meanwhile, will welcome wide receiver T.Y. Hilton back to the practice field on Wednesday with the hope he can soon be activated off injured reserve.

Hilton had to undergo neck surgery ahead of the 2021 NFL season

"Certainly excited to have T.Y. back in the fold and out on the field," said Colts coach Frank Reich. 

"Obviously that's a big, emotional boost to the team."

The Colts now have a three-week window in which they can activate four-time Pro Bowler Hilton off injured reserve, with the prospect of him facing the Texans not yet ruled out.