Texans star receiver Nico Collins is dealing with a hamstring injury “week to week.”

The Houston Texans improved to 4-1 with a thrilling win over Buffalo on Sunday and marked their best start since the start of the 2012 season with five straight wins. But the victory came at a price as Nico Collins, who had 567 yards receiving the top player in the NFL, injured his hamstring and will likely miss this week.

Collins skipped Sunday's 23-20 win after hauling in a 67-yard reception late in the first quarter.

Coach DeMeco Ryans didn't directly answer a question about whether he would play Sunday, but his answer made it seem like Houston could be without him for a while.

“He's in good spirits, (but) with the Achilles tendon, obviously it'll take a few weeks for him to get a hamstring injury,” Ryans said Monday. “So we’ll evaluate that week by week to see when we can get him back.”

If he can't play on Sunday, it will put an even greater strain on an offense that is already without running back Joe Mixon. He rushed for 159 yards in the team's opener, but was injured in Week 2 and hasn't played since. Ryans said he was feeling better but wasn't sure when he would return.

The Texans built a 20-3 lead against the Bills, but struggled offensively for most of the second half with Collins out.

Quarterback CJ Stroud threw an interception and had his first fumble of the season on a sack in the fourth quarter, allowing the Bills to tie the score before Ka'imi Fairbairn secured the victory with a 59-yard field goal on the final play of the game.

“The first half went really well. We moved the ball the way we wanted, let the ball run,” Stroud said. “In the second half… we shot ourselves in the foot again and only took penalties. I missed a few errors on my shots and had two turnovers. When you play like that, you give them a chance to come back.”

Stefon Diggs led the Texans with six receptions for 82 yards on Sunday, and Stroud praised his play and the contributions of the rest of the team's receivers. But he admitted that losing Collins really changed things.

“I think he’s the best receiver in football,” Stroud said. “If he leaves the game it will definitely be difficult for us. Many things are attributed to him and planned for him.”

Ryans agreed, saying it will take a team effort to make up for the loss if Collins can't play.

“Nobody has to go out and be Nico,” Ryans said. “There's a Nico, he did great, and whoever is next when your number is called makes the plays you're supposed to make.”

The Texans will have to wait to see if Collins has recovered before traveling to New England for their first consecutive road game on Sunday. If he can't go, Diggs and Tank Dell will have to do more against the Patriots to make up the deficit.

Reporting by The Associated Press.

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