HOUSTON — Just when it appears that Texans All-Pro defensive end J.J. Watt has limitations to his ability to wreak havoc on the field, Watt does something to prove that he isn’t one for abiding by the restrictions.

Watt highlighted a destructive performance with an interception return for a touchdown, giving the Houston Texans a lead they would not relinquish in their 23-17 victory over the Buffalo Bills on Sunday at NRG Stadium.

Moments after Bills linebacker Nigel Bradham picked off Texans quarterback Ryan Fitzpatrick on the first play of the second half, Watt stepped in front of an EJ Manuel pass intended for running back Fred Jackson. Watt made a leaping catch and sprinted 80 yards for the sixth-longest interception return by a defensive lineman in NFL history.

“He made a play,” Bills coach Doug Marrone said. “One of the keys was to make sure he wasn’t going to make that big, disruptive play prior to the game and he did. He made a lot of plays.”

Watt supplied the Texans a 14-10 lead with his most memorable defensive play, but that wasn’t his lone contribution. He harassed Manuel throughout, finishing with nine quarterback hits to accompany his five tackles, one pass defended and the interception. He was penalized twice in the first half for low hits on Manuel that seemed to stoked his fire.

“The way the stadium exploded … that’s a game-changing type of play and that’s what you want as a defensive player,” Watt said of his interception return. “That’s what you live for. That’s why you play the game, for feelings like that.”

The nine quarterback hits represented a single-game career best for Watt. Entering Sunday, no NFL player had more than eight this season.

Manuel finished 21 of 44 for 225 yards with two touchdowns and a pair of interceptions. His second pick came with 67 seconds remaining and after the Bills (2-2) surged into Houston (3-1) territory. Texans cornerback Darryl Morris snagged an errant pass to snuff that final threat. Watt applied the pressure on Manuel to force the hurried throw.

What the Texans said:

“It’s emotional. It’s great to see all my former teammates after the game and talk to them. They’re obviously not happy with losing.” — QB Ryan Fitzpatrick, who spent four seasons (2009-12) with Buffalo.

What the Bills said:

“I think we are a team. And we play together as a team. And we win and lose as a team. Period.” — Coach Doug Marrone on if his offense let down his defense, which limited the Texans to 37 rushing yards.

What we learned about the Texans:

1. Kicker Randy Bullock has developed into precisely the weapon the Texans’ limited offense needs. The Texans used a fifth-round pick on Bullock in 2012 and have waited a while to cash in on their investment. And after nailing a pair of 50-plus-yard field goals in the fourth quarter against the Bills, Bullock is 8-for-9 on field goals this season, including 5-for-5 beyond 40 yards.

2. The Texans’ inability to run the ball consistently continues to be a growing concern. After a one-game injury hiatus, running back Arian Foster returned to ineffective results, mustering just six yards on eight carries with a long run of four yards. As a team the Texans are averaging just 3.6 yards per carry and have only two rushing touchdowns in four games.

–DE J.J. Watt finished with a career-high nine quarterback hits to go along with five tackles, one pass defensed and an 80-yard interception return for a touchdown, the sixth-longest by a defensive lineman in NFL history. Watt joined Texans LB coach Mike Vrabel as the second player since the merger to record an interception return for a score and a receiving touchdown in the same season. “Unbelievable. Just unbelievable,” Texans owner Bob McNair said. “I mean, what’s next?”

–NF Ryan Pickett earned the start after signing with the team earlier this week and finished with one tackle. Pickett started all 16 games in each of the last two seasons with the Packers. “I think I did OK,” Picket said. “I had to knock off a little rust but I think I did good.”

–CB Darryl Morris posted four tackles, one TFL, three passes defensed and an interception filling the void left by injured CB A.J. Bouye. Morris, an undrafted free agent who played for the 49ers last season, was signed off waivers just prior to the start of the season. “I was put in a situation to make plays and I made plays,” Morris said.

What we learned about the Bills:

1. Despite his ongoing struggles, quarterback EJ Manuel is projecting an air of confidence. Manuel was guilty of several poor throws and in the postgame presser, coach Doug Marrone was asked if he considered inserting backup Kyle Orton. When taken to task over his performance, Manuel was mature and unshaken. “I think it’s part of maturing as a man and as a quarterback. Nobody said it was going to be easy, plain and simple.”

2. The Bills’ rushing defense is absolutely legitimate. After entering Sunday ranked sixth in the NFL in rushing yards per play allowed, the Bills allowed the Texans to rush for just 37 yards on 24 carries, including 17 yards allowed on 10 carries when the Texans attempted to control the clock in the fourth quarter. “We believe in ourselves and we believe that we are a top-five defense in the NFL,” Bills cornerback Leodis McKelvin said.

–DT Kyle Williams was lost to a knee injury in the second half after his pass deflection led to an interception by LB Nigel Bradham on the first play of the second half. Williams finished with two tackles, including one for lost yardage and has 11 tackles (three TFLs) on the season. “When you lose a player during that time of the game it’s always difficult,” Bills coach Doug Marrone said.

–QB EJ Manuel attempted a career-high 44 pass attempts, completing 21 for 225 yards and two touchdowns with two interceptions. Despite their proficiency on the ground — the Bills rushed for 96 yards on 23 carries — the Bills nearly attempted twice as many passes as rushes. “I think that when we get into games where we throw as much as we did, that gets us in trouble,” Bills coach Doug Marrone said.

–RB C.J. Spiller had 21 touches for 166 yards but did not score for the inconsistent Bills offense. After scoring on consecutive possessions in the second quarter, the Bills punted five times and turned the ball over once during their ensuing six possessions excluding the end of the first half. “We had out chances; they just made the plays you have to make on the defensive side of the ball to come away with the win.”