Part of the Texans' overhauled secondary, newly acquired cornerbacks Bradley Roby and Lonnie Johnson Jr. are off to a slow start with the AFC South franchise.

Both were sidelined for the majority of the spring with soft-tissue injuries.

Roby returned for a mandatory minicamp. Johnson flashed potential when he practiced during an organized team activity, but missed a lot of practices.

Signed to a one-year, $10 million, prove-it contract that included $9.5 million guaranteed, Roby is a former Denver Broncos first-round draft pick. He chose the Texans over a three-year, $30 million offer from the Pittsburgh Steelers and a one-year, $9 million offer from the San Francisco 49ers.

Roby limited Kansas City Chiefs wide receiver Tyreek Hill to four catches for 23 yards on eight targets in a game last season.

With the Texans so far, though, it's been slow going.

"He hasn't done much, so we'll just have to see in training camp," Texans coach Bill O'Brien said.

Big, strong and fast at 6-2, 213 pounds, Johnson fits the prototype for the position with 4.39 speed in the 40-yard dash.

The second-round draft pick from Kentucky has missed a lot of time.

O'Brien was noncommittal on his availability for training camp even though Johnson is expected to be ready for the start of camp.

"I don't know," O'Brien said when asked if Johnson will be available. "No idea."

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