Arch Manning is in concussion protocol and did not practice Monday for Texas, Longhorns coach Steve Sarkisian said late Monday morning.

“We’ll have more information as the week goes,” Sarkisian said in his weekly news conference.

Manning, Texas’ starting quarterback, went down in overtime of the Longhorns’ come-from-behind win against Mississippi State on Saturday after a 13-yard scramble put Texas at the Bulldogs’ 12-yard line. Manning hit his head on the ground while diving forward and spent the rest of the game in the injury tent.

In his absence, backup Matthew Caldwell entered the game and connected with Emmett Mosley V in the right corner of the end zone for the game-winning touchdown.

The No. 20 Longhorns host a hot No. 9 Vanderbilt team this week at Darrell K Royal Texas Memorial Stadium, where Manning’s status will no doubt be the biggest storyline of the week.

Manning and Texas’ offense took their lumps to start the season and, in some ways, are still trying to hit their stride. But Manning threw for a career-high 346 yards and three touchdowns (with one interception) against the Bulldogs as he led the Longhorns in comeback fashion after Texas trailed by as many as 17 points in the fourth quarter.

For the season, Manning is 143-for-235 passing for 1,795 yards and 15 touchdowns against six interceptions through eight games.

Sarkisian said he submitted a few plays from Saturday’s game to the SEC office, as is customary for coaches, and hasn’t heard back about Manning’s hit.

“The last thing I want to do on game day is be complaining to the officials the whole time, and so I just want to make sure that I know how we’re officiating certain plays so that I can complain when it’s appropriate,” Sarkisian said.

“So a lot of the plays we send in is not to say, ‘See I told you so.’ It’s to get back, ‘No, this is why it wasn’t called,’ or ‘Yes, it probably should have been called.’ And so I haven’t gotten a ruling back on that yet.”

Asked about the plan for Manning this week, Sarkisian didn’t have much to offer.

“That’s for the doctors,” he said.

The SEC requires Texas to release an injury report Wednesday. Should Caldwell have to play in Manning’s place, Sarkisian sounded confident in his backup’s abilities.

“I think the good thing for Matt, he’s a very even-keeled guy. I thought he had a great practice (Monday),” Sarkisian said. “The players have a lot of confidence in him. His maturity, his approach, he’s very engaged even when he doesn’t play.

“He’s making the most of his opportunities. He’s played well every time that we’ve put him in the game. … What gives me confidence is who he’s been. I feel very comfortable with Matt whenever he’s in the ballgame.”

For the season, Caldwell is just eight of 11 passing for 85 yards and one touchdown in five games. The Troy transfer went 141-for-223 passing for 1,608 yards and 13 touchdowns for the Trojans last season.

Vanderbilt has the nation’s No. 31 defense heading into Saturday.