HOUSTON (AP) When the Houston Texans host the Tennessee Titans on Sunday, it will be the first time since 2010 they'll play without J.J. Watt.
A person familiar with Watt's condition said the star defensive lineman he had back surgery Thursday and it is expected to miss the rest of the season. The person spoke to The Associated Press on Thursday night on condition of anonymity because the team hasn't announced the surgery.
Watt was placed on the injured reserve Wednesday. It's his second back surgery in two months after he missed training camp and Houston's four preseason games after surgery in July to repair a herniated disk. He will miss a game for the first time in his career after starting 83 straight games since he was drafted in 2011.
Watt's loss is a huge blow to a team looking to bounce back after a 27-0 loss to New England last week. The Texans know that one person can't replace what Watt brought to their team, but coach Bill O'Brien expects everyone to pitch in to help make up for his absence.
O'Brien was with the Patriots in 2008 when they went 11-5 despite playing without Tom Brady for all but one game.
''I've been around teams where a top player goes down and the mentality of the team, which needs to be the mentality of a team, is that if a good player goes down - if any player goes down - the next guy has to step up,'' he said. ''That's the mentality of this team.''
Defensive coordinator Romeo Crennel wouldn't say who would start in Watt's place. But he did say that other stars of his defense like Jadeveon Clowney and Whitney Mercilus will have to continue to improve to keep the defense afloat.
Tennessee coach Mike Mularkey said their game plan won't change with Watt out and knows Houston's defense has plenty of other threats the Titans will have to deal with.
''They have a pretty good front there, so we have a lot of guys we have to handle up there,'' he said.
The Titans have struggled against Houston the past two seasons and have lost four in a row in the series. Tennessee defensive tackle Jurrell Casey knows that if they hope to contend in the AFC South they'll have to figure out a way to beat the Texans.
''It's something that's been haunting us for the last couple years ... it's a ... divisional opponent that's been on top of our division for a long time,'' he said. ''If we want to take our division by storm, it's got to start this week.''
Some things to know about the Titans-Texans game:
ROAD WARRIOR: Marcus Mariota has been at his best away from Tennessee so far in his young NFL career. In seven games on the road, Mariota has thrown for 1,612 yards with 12 touchdowns with only two interceptions for a 104.9 passer rating. He also has a rushing TD and caught a TD catch on the road. This will be his first game in Houston, and Mariota has five TD passes with a 92.6 passer rating in his last three games against divisional opponents. Mariota isn't sure why he's played so much better on the road, where three of his four career victories have come.
''That's going to have to change,'' Mariota said. ''Really, again, I've got to continue just to prepare like any other game, focus on what I have to do and what this team asks me to do, and just continue to be a better player each and every single day.''
NO EXCUSES: Houston quarterback Brock Osweiler is in his fourth year in the NFL, but spent most of that time as a backup and has just 10 career starts. He's struggled so far this season, throwing four interceptions and three touchdown passes. He isn't using his inexperience as an excuse.
''I don't use my lack of starts as an excuse for anything,'' he said. ''I expect myself to play at an extremely high level. I have great confidence in my abilities and what I can do, and I have great confidence in the teammates around me to help me do my job. I'm never going to use my lack of starts for an excuse or say: `I'll figure it out eventually' or anything like that.''
OFFENSIVE BOOST: The Titans are hoping tight end Delanie Walker is back against the Texans; he missed the Oakland game with a right hamstring injury. He had a career season last year with 94 catches for 1,088 yards, and Walker has been the Titans' biggest deep threat so far, with the longest reception this season at 32 yards. Barring a setback, wide receiver Kendall Wright also should make his season debut in Houston. Wright caught Mariota's first career touchdown pass but has been hampered by injuries over the past season. His return would provide a speedy boost to the offense.
RETURNING TO HOUSTON: This will be the second straight season Andre Johnson has returned to the town where he played his first 12 NFL seasons and still keeps a home. Johnson had six catches for 77 yards and two TDs when he played the Texans as a member of the Indianapolis Colts last season, and he said it's fun to go back home.
''It'll be good to go back and see some faces I haven't seen in a little while,'' Johnson said.
AP Sports Writer Teresa Walker contributed to this report.
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