HOUSTON — The Houston Texans are 4-2 and remain atop the AFC South standings after rallying for an overtime win against the Colts on Sunday night.

But there are plenty of ways they can improve before next Monday’s trip to Denver after playing three lackluster quarters in the victory.

Quarterback Brock Osweiler and the offense struggled to get going early for the second straight game, falling behind 13-0 after trailing 24-0 early last week in a loss to Minnesota. Questions remain about Osweiler after he’s thrown as many interceptions (8) as touchdowns this season.

“What happened (Sunday) was we either didn’t start the drive with a positive play or we did and then we would get a penalty or some type of sack or (tackle for loss) that would set us back in the drive,” O’Brien said. “We have to eliminate those. We have to eliminate penalties, eliminate the things that make us an inconsistent offense and kind of try to bottle some of the things we did late in the game to be more consistent.”

The offense rebounded late on Sunday, with Osweiler throwing two touchdown passes in the last three minutes to erase a 14-point deficit and force overtime. He then directed a drive that ended with the winning field goal.

Critics have been hard on Osweiler because of his inconsistent play after he signed a $72 million contract to join the Texans. He isn’t sure what Sunday’s comeback win showed about him, but hopes people understand the work he’s putting in to get better.

“The struggles we’ve had aren’t due to a lack of preparation or a lack of confidence or anything like that,” he said. “We come in here … and we prepare extremely hard all week long to be successful. I understand there (have) been some frustrating moments, but this team showed a lot of heart (Sunday), and I hope people saw that, as well.”

O’Brien thinks a key to the offense improving is getting running back Lamar Miller more touches. Miller was the star of the win over the Colts, finishing with a season-high 149 yards rushing with a touchdown and adding a receiving score.

He’s already been very involved in the offense and his 125 carries rank second in the NFL, but O’Brien still want to give him more opportunities.

“The more we get Lamar the ball, probably the better,” O’Brien said. “Because I think when he touches the ball usually good things happen. Whether it’s in the run or the passing game or screens or however we get him the ball, I think it’s probably going to be good for the Houston Texans.”

Houston’s pass rush has remained solid despite the loss of last year’s NFL Defensive Player of the Year, J.J. Watt. However, the Texans are looking to shore up their run game after Frank Gore became the first Indianapolis player to rush for 100 yards since 2012.

“There were times where we looked like we were really doing a great job stopping the run, but too many double-digit yardage runs, too many double-digit drives,” O’Brien said.

The Texans will also have to make some adjustments this week after cornerback Kevin Johnson injured his foot Sunday and is out indefinitely. Houston has had a lot of injuries to the secondary recently.

The Texans opened Sunday’s game without starting cornerback Kareem Jackson and safety Quintin Demps before cornerback Johnathan Joseph left with a forearm injury.

Houston will likely get those three players back this week, but O’Brien wouldn’t provide any details on when Johnson might return.

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