INDIANAPOLIS -- As the Houston Texans built their roster this offseason, the focus was on rebuilding the culture in the organization, something team CEO and chairman Cal McNair believed started at the top with new general manager Nick Caserio and coach David Culley.

After making those hires this offseason, the Texans overhauled the roster, adding veteran players through trades and free agency, mostly signing players to one- or two-year deals.

But despite the makeup of the roster, with players who have plenty of NFL experience, after the Texans (1-5) lost 31-3 to the Indianapolis Colts (2-4), wide receiver Brandin Cooks called this an “undisciplined team.”

“It’s been going on since Game 1, and we still haven’t fixed it,” Cooks said. “That’s an individual thing.”

The Texans opened the game Sunday with a false start penalty on the first play of the game. While this was by far Houston’s best game in terms of penalty yards, Culley still pointed to that area and a large number of mental mistakes as the reason the Texans lost their fifth game in a row. Houston has been outscored 71-3 in its past two road games.

“I think that’s something you’ve got to take on individually, to be honest with you,” Cooks said. “You can’t make anyone disciplined. You’ve got to want to be disciplined. You’ve got to practice that way, but you’ve got to be in the meeting room that way. You’ve got to take care of your body.

“Success is not a gimmick, discipline is not a gimmick. It’s about everyday life choice. It’s about, deep down inside, individually, do you want to be that or not? It’s as simple as that. We can’t make our teammates, we can’t make anyone else, do that. You’ve got to do it by yourself.”

The team didn’t do that Sunday, and running back Mark Ingram II said it led to “bad football” from the Texans in the loss.

"We emphasized it all week,” Ingram said. “Coach Culley, even at halftime, was like, ‘first play of the day, we have a penalty.’ That’s just bad football. Turning the ball over, that’s bad football. Allowing big plays, that’s bad football. Those are all things he emphasized all week long. He even emphasized it at halftime, and we came out and got a stop and we got a turnover.

“We’re not pointing fingers, but we just know turnovers, penalties, unforced errors, that’s bad football and [those are] ways that will keep you getting beat.”

One turnover was rookie quarterback Davis Mills’ first interception of the game, ending Houston’s first possession of the second half after one play.

“Probably needed to hit my checkdown or try to make a play with my feet,” he said.

Instead, Davis, who threw two interceptions on the day, forced a throw.

“I thought the first half, [Mills] played well, just like he had played the last game,” Culley said. “In the second half, the turnover, it basically flipped the whole game around for us with that [first interception].

“But again, I go back to critical mistakes that we’re making at critical times, and that INT at that time was a big momentum changer during the game. And we can’t do that.”

Culley pointed to the mental mistakes made on defense -- "guys not being in the right place" -- as another reason the Texans allowed some explosive plays by the Colts’ offense.

“[The mental mistakes are] very frustrating,” Culley said. "Those are things that in this league, to win … we talked about knocking the door down. The only way you’re going to get those wins, you’ve got to do that by being prepared and mentally doing the right thing, and we’re not consistently doing that. And we’re doing it at critical times, making those kinds of mistakes.”

And even though Culley has made avoiding mistakes and penalties a point of emphasis to his team, Ingram said, it’s now a matter of execution for a team tied for last place in the AFC South.

“You can emphasize it all you want, but until you have the discipline and know the snap count and know the cadence of the quarterback’s tone and what we’re going on, you’re just going to have those errors,” Ingram said. “Every individual person has to be accountable, be disciplined, be fundamentally sound.

“Individually it’s just the focus, it’s the discipline, it's the small attention to details, and we have to continue to get better at that if we want to turn this thing around.”