Two weeks of training camp in West Virginia and one preseason win later, the Texans arrived at NRG Stadium while most of the city was still sound asleep in the pitch-dark hours early Friday morning.

After a few hours of rest, if any, most were back at the stadium for another day of work following the 17-10 win in Kansas City.

"This is really the grind of camp," head coach Bill O'Brien said. "People who talk about the grind of camp after the first week, I mean, we had just started. This is where you get back from a game at 4 a.m. You're in here today, got to get your rehab done and your weightlifting and all those things."

Players will get their official welcome to Houston on Saturday, when they hit the practice fields at the Houston Methodist Training Center in the stifling August heat. As the Texans head into the second game of preseason against the San Francisco 49ers, they will get Sunday off before a busy week of work. The much-anticipated joint practices will give players new faces and techniques to work against in camp.

"Towards the end of the week, on Wednesday and Thursday, 49ers will be here," O'Brien said. "It will be great competition, it will break up the monotony, it gives our players a chance to see different schemes, different skill sets. It gives our coaches a chance to work against different coaches and coaches we really respect so it's just always good."

In every season with O'Brien as head coach, the Texans have held joint practices with other teams in camp. The Texans previously scrimmaged against the 49ers at their Santa Clara facility in 2016.

"I think the joint practices are really good," O'Brien said. "I've always enjoyed them. I enjoy working with the other coaches on setting up the practice plan."

Last year, the Texans practiced against the New England Patriots in West Virginia and against the Saints in New Orleans. In 2014, Houston hosted the Atlanta Falcons for joint practice. During filming of HBO's Hard Knocks in 2015, the team traveled to Richmond, Virginia to scrimmage against Washington at camp. The Texans worked against both the Saints at home and the 49ers on the road in 2016.