Mississippi State defensive end Montez Sweat and Ohio State cornerback Kendall Sheffield are visiting the Texans on Wednesday, according to league sources not authorized to speak publicly.
Sweat, a 6-6, 260-pound pass rusher, set an NFL scouting combine record for defensive linemen when he ran the 40-yard dash officially in 4.41 seconds.
That set a record that dates back to 2003.
Just one running back, Oklahoma State runner Justice Hill, ran faster than Sweat.
A two-time first-team All-Southeastern Conference selection, Sweat recorded a dozen sacks last season and 10 1/2 sacks two years ago.
Sweat has a preexisting heart condition, but that isn't expected to significantly affect his draft stock.