The Houston Texans began their rookie minicamp Friday with 16 undrafted signees, 16 tryout players and eight first- or second-year players with practice squad eligibility. Here are nine notes and observations from the day:

The message Texans coach Bill O'Brien likes to give his rookies is that they need to be coachable, be good teammates and that what they did in college is in the past. All that matters now is what they do starting now. "Basically since the end of their college season they've been somewhat of a man without a country, meaning, they hired an agent, a lot of these guys hired an agent. The agent placed them maybe in a workout facility. They were kind of making sure that they were taking care of their own skill set as it relates to the combine, those types of drills, the Senior Bowl and all those things. So, the first thing they need to do is realize that they're back to being a part of a team and what it means to be a Houston Texan." Based on locker room interviews, the message was heard. The rookies were careful to repeat their main talking points.

Receiver Keith Mumphery was a fifth-round pick last weekend and stood out to me on the practice field. His repertoire included a nice one-handed catch during one drill. He looked to be in shape and moving well. O'Brien has talked a lot this offseason about wanting to see improvement on special teams and he expects Mumphery to learn the kickoff, kickoff coverage, punt and punt return teams. I asked Mumphery about playing special teams and he said, "My main goal is to be coachable and do whatever the coaches ask."

Defensive end James Rouse left practice early on a cart. The injury appeared to be in his right ankle area. Rouse, a Marshall product, was one of the Texans' 16 undrafted free-agent signees.

Baylor coach Art Briles stopped by practice. Briles has been an occasional visitor of Texans camp practices.

At rookie camp, the first-round pick is the top dog and Texans' first-round pick Kevin Johnson stood out positively. He had a strong day facing third-round pick Jaelen Strong and EZ Nwachukwu, a fixture on the Texans' practice squad for the past two seasons. I'd heard a lot about Johnson's physicality once he was drafted and it was on display during Friday's practice. On one play it got him in a little bit of hot water since these are non-contact practices.

Lynden Trail is physically impressive and looks the part of an NFL player. His 6-foot-7 frame made it tough for tryout quarterback Kevin Rodgers to throw over him. Trail had a batted pass during an 11-on-11 drill.

The temperature was in the high 80s, and there was cloud cover and a nice breeze at practice. A few players cramped up. That Houston humidity can be challenging.

Le'Vander Liggins is in camp as a tryout player and made impressive plays Friday. He's a 5-foot-11, 190-pound defensive back from Louisiana Tech.