Mariota said his knee got twisted up underneath him on a sack by linebacker Jamie Collins. It's a play where the quarterback shouldn't have been under such pressure, interim coach Mike Mularkey said, but running back Antonio Andrews made a mistake in protection.
Mariota said he was not sure of the extent of the injury, but once he had a brace on the knee, he wanted to return to action. Mularkey and the Titans' staff decided to err on the side of caution.
"The training staff felt that if I wasn't at 100 percent, it wouldn't have been good for me to be out there," Mariota said. "[Pain] wasn't a huge factor. I think it was more the stableness of it."
"We're going to see what it is tomorrow. I don't expect to be out the rest of the year."
Mularkey didn't seem overly concerned about the injury.
"I don't think it's serious, no," he said. "Actually, we were tempted to maybe put a brace on him and discussed putting him back in. We thought in the best interest for him and our team and where we're at right now, the best thing is to hold him."
Zach Mettenberger relieved Mariota and hit on 20 of 28 passes for 242 yards, two touchdowns and two interceptions.
The No. 2 pick in the 2015 draft out of Oregon sprained his left knee in the Titans' Oct. 18 loss to Miami on an illegal hit by Olivier Vernon. He finished that game, but then missed two weeks.
Mariota was an offensive captain for the first time and said it was an incredible honor. He said it was his understanding that the players and Mularkey decided on the role and the team wanted to add an offensive captain after running back Dexter McCluster was lost for the year with a wrist injury suffered last week in New York against the Jets.
The Titans play at home against Houston on Dec. 27 before finishing the season at Indianapolis on Jan. 3.
Mariota leaves game vs. Pats with knee injury
Titans QB Marcus Mariota leaves the game against the Patriots with a knee injury after being sacked by LB Jamie Collins.