Since most players make their biggest improvement between their first and second seasons, the Texans are eager to see just how good strong safety D.J. Swearinger can be.

Swearinger, a second-round pick in 2013, started 10 games as a rookie, finishing sixth on the defense with 83 tackles.

Swearinger has a new defensive coordinator in Romeo Crennel and a new position coach in John Butler, and he's determined to show the kind of improvement many second-year players make.

"I got a lot of experience playing against a lot of great players," Swearinger said after practice Wednesday. "Players that helped me last year were Ed (Reed), Danieal Manning and J Joe (Johnathan Joseph)."

Joseph, a nine-year veteran starting at cornerback for a fourth season with the Texans, is the only player returning among the three Swearinger mentioned.

"Those guys helped me a lot with my techniques and my knowledge of the game," he said. "I wouldn't say that I'm a rookie again (with a new staff and system). I'd say it's just me having to learn a new system."

The Texans also have a demanding new coach in Bill O'Brien, who has long, tough practices in training camp.

"Any time you lose 14 games, it's a vibe that we have to work hard, and he's making us work hard," Swearinger said. "We're buying in, keeping the team first.

"As a defender, you always have to have a chip on your shoulder. You want to force turnovers. You always want to be the top defense."

As a rookie, Swearinger was known as a hard hitter who played better near the line of scrimmage. Now that he has a year of experience, he's moving around and learning both positions under Crennel, who expects him to improve on pass coverage.

Crennel owns five Super Bowl rings as a position coach and defensive coordinator. He likes for his players to be versatile and learn more than one position.

"There are a couple of guys like myself that play dual positions," said Swearinger, who can play either safety spot. "I'm a safety, and if I know what the D-line is doing and what the linebacker's doing, it helps me because I know where they are, and I know I can take my chances and gamble."

Swearinger's teammates have been impressed with his performance.

"D.J. shows tremendous upside," Joseph said. "We're looking for him to make strides.

"I think he's done a great job. He comes out here every day, works hard and gets better."