HOUSTON -- As Houston Texans quarterback Brock Osweiler works to improve his passing game, he'll need as much help as he can get from his offensive line.

That got more complicated on Monday night when the Texans lost starting right tackle Derek Newton for the rest of the season with injuries to both knees. ESPN's Adam Schefter reported that Newton tore both patellar tendons in the loss to the Denver Broncos.

Leading up to that game, Texans head coach Bill O'Brien said Houston had to gameplan for the Broncos' "disruptive" front seven, especially outside linebacker Von Miller. Denver entered the game leading the league in sacks.

But even after the first-quarter loss of Newton, who was replaced by a combination of veteran tackle Chris Clark (83 percent of the Texans’ offensive snaps) and tackle Kendall Lamm (19 percent), the offensive line played well; Osweiler was only sacked once.

"I thought the line did a decent job all night, I really did," O'Brien said. "I thought they battled hard. They competed."

Houston was able to run the ball well behind the line, as running backs Lamar Miller and Alfred Blue combined for 135 yards on 22 carries.

But there is one concern if the line struggles without Newton at right tackle. Because Osweiler is still in his first season in O'Brien's system and is still learning, he needs as much time as the line can give him to make decisions at the line of scrimmage.

"I think that Brock is working very hard to understand our system and how it applies to different defenses," O'Brien said. "I don't think it's easy to just jump right in and quickly be able to apply a brand-new system to what a top-level defense is doing."

Osweiler struggled against pressure against the Broncos on Monday, the same way he has all season. Against four or fewer pass rushers this season, Osweiler has completed 62 percent of his passes, while that number drops to 47 percent with five or more rushers. His QBR goes from 59 to 24 in the same scenario, and his yards per attempt drops from 6.3 (with four or fewer rushers) to 4.1 (five or more), according to ESPN Stats & Information.

The Texans also dealt with injuries at the tackle spot when left tackle Duane Brown missed the first five games of the season while recovering from a quad injury he suffered at the end of last season.

On Monday night against the Broncos, Osweiler's longest completion was a 13-yard pass to rookie receiver Will Fuller. Regardless of whether it was because he didn't have time or because the receivers couldn't get open, Osweiler was consistently unable to connect with his receivers downfield. He finished 0-for-7 on throws that were at least 15 yards or more downfield.

"[Throwing downfield] is part of this offense," Osweiler said on Monday night. "We try to hit our running backs underneath. We try to hit our tight ends underneath. We like to push the football down the field, and we weren't able to do that."