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Carolina Panthers linebacker Luke Kuechly could miss the first game of his NFL career Sunday.

Kuechly, who’s in the league’s concussion protocol, is listed as doubtful for Week 2 against the Texans. On Saturday, the Panthers will give him a chance to clear the protocol’s final stages, which include passing tests from an independent neurologist.

“We’re going to weigh all the possibilities,” coach Ron Rivera said Friday. “The other thing to look at is who we play coming up … As we look at the schedule as it comes up, we’ve got four conference games, and two of those are division games. There’s a lot of things that are going to weigh into this.

“I’m like Luke, I’m chomping at the bit, but at the same time, you have to be careful.”

While Rivera left open the possibility the Panthers could hold out Kuechly even if he’s cleared, he also said:

“Whatever the independent says is what we’re going with.”

During his three years at Boston College and through three-plus seasons as a pro, Kuechly has never missed a game. He’s played 93 percent of potential snaps since coming to Carolina while making 49 straight regular-season starts.

A.J. Klein, who replaced Kuechly after he suffered his first concussion in the NFL last week against the Jaguars, would be in line to make his 11th career start.

“You’re talking about probably the best defensive player in the NFL. He was defensive player of the [year] two years ago, now the highest-paid [middle] linebacker in NFL history. He’s that for a reason. He’s the best linebacker in the NFL,” Klein said Friday.

“But the opportunity for me to be able to learn from him for these last two years has helped me. It’s going to help me on Sunday.”

Offensive tackle Daryl Williams, who will miss two to four weeks after spraining his MCL in Week 1, is the only Carolina player ruled out against the Texans.

Defensive tackle Star Lotulelei was limited in practice for a third straight day, and there’s no guarantee he’ll make his season debut Sunday.

Lotulelei, defensive end Wes Horton and tight end Richie Brockel are listed as questionable. Brockel on Friday practiced for the first time since he injured his shoulder against the Dolphins nearly four weeks ago.