HOUSTON -- Chased yet rarely caught by a frustrated Houston Texans defense Sunday, San Diego Chargers veteran quarterback Philip Rivers lumbered inside and outside of the pocket to uncork a series of accurate spirals with his trademark unorthodox delivery.
On a day where the Texans needed them to be stellar because of the ineptitude of quarterback Brock Osweiler, the defense was ordinary and too frequently remained a step behind a strong-armed quarterback who put on a clinic at how to play the position.
"We just beat ourselves," Texans cornerback A.J. Bouye said. "We didn't play well enough."
Rivers completed 22 of 30 passes for 242 yards, three touchdowns and one interception for a 116.3 passer rating during a 21-13 victory over the Texans at NRG Stadium.
Rivers' deft touch passes and ability to get the football out of his hand to avoid sacks prevented the Texans' defense from harassing him into mistakes. He was only sacked once and hit five times, unfazed by the Texans' pass rush.
"They're tough, but there were times we were back there on him a lot," Texans defensive end Jadeveon Clowney said. "I felt like we were hitting him a lot, getting to him. We should've kept coming with a lot more pressure out there, but the game got away from us."
During the second quarter, Rivers grabbed the momentum and never relinquished it from his grip. Rivers found wide receiver Dontrelle Inman on a fly pattern for a 52-yard touchdown in which strong safety Quintin Demps got juked and stumbled as Inman accelerated past him.
"It was a double move," Demps said. "I got to play it better."
During the first half, Rivers completed 13 of 16 passes for 148 yards, two touchdowns and no interceptions for a 144.8 passer rating.
It was a clear step backward for a Texans defense that's going to be leaned on heavily as Osweiler continues to struggle with turnovers as he threw three interceptions Sunday and now has 13 for the season.
"We didn't start fast as a team," Clowney said. "We should've won the game. I don't think we're playing up to what we're used to playing like the past few weeks, and we have to get back to that."
Behind the strength of Rivers' game, the Chargers were efficient on offense. It wasn't that the Texans were overwhelmed by Rivers as they allowed 302 yards of total offense and 18 first downs, but he was good enough to beat them.
"Great quarterback, probably one of the best in the league," Texans free safety Andre Hal said. "He did a good job of checking off at the line of scrimmage. He played a great game."
Sacked by inside linebacker Benardrick McKinney in the first half on a blitz, Rivers wasn't sacked in the second half. Hit four times in the first half, he was hit just once after halftime.
"I was riding in (Sunday) reading (The Houston Chronicle) and reading how they're fifth in defense," Rivers said. "I was reading all the different things you know about them, but I don't pay attention to some of those statistics. We knew we were coming into a good defense."
The Texans missed outside linebacker John Simon's gritty presence. Simon missed the game with a chest injury. He ranks second on the defense with 50 tackles and 3.5 sacks.
Without Simon, the Texans had to use different personnel packages. Backup nose tackle D.J. Reader played defensive end and undrafted rookie defensive end Ufomba Kamalu made his NFL debut. Clowney alternated between outside linebacker and defensive end, operating out of two-point and three-point stances. One time, he lined up at inside linebacker and shot through the center-guard gap.
"John Simon is a great linebacker for us," McKinney said. "We're sorry he couldn't play this game."
The Texans were stout against the run, surrendering just 68 yards on the ground on 18 carries as they limited Melvin Gordon to 70 yards on 17 carries. However, the bulk of the damage was done through the air.
"We shot ourselves in the foot a little bit, but they played a good football game," nose tackle Vince Wilfork said. "We didn't make enough plays."
The Texans' defense was also plagued by short fields created by turnovers, which included a lost fumble by running back Lamar Miller in the third quarter.
Unlike previous games where they were able to overcome those adverse circumstances, the Chargers capitalized as an interception by cornerback Casey Hayward in the second quarter led to a Tyrell Williams' touchdown catch.
The sudden-change situations impacted the Texans' defense.
"Very difficult, it puts us in tough spots," Clowney said. "You have to bow up. We did it a lot against Oakland. We should've bowed up against them when the offense turned the ball over.
"Defense, we have to play better. We can't have any letdowns. We set the tone, and we let this thing get away from us."