The scheduled visits were earlier reported by KRIV-TV and the Houston Chronicle.
The Texans sent coach Bill O'Brien and general manager Rick Smith to both players' pro days. Cal McNair, the Texans' vice chairman and chief operating officer, also attended Manziel's pro day (as did former President George H.W. Bush).
Houston has the first pick in this year's draft. The Texans have a need at quarterback, among other positions, and have said they will draft a quarterback at some point, having traded Matt Schaub (who started 2013 as the Texans' top quarterback) to the Raiders.
Houston signed veteran quarterback Ryan Fitzpatrick in free agency and has T.J. Yates and Case Keenum on the roster.
A large Texans contingent attended South Carolina's pro day last week to see defensive end Jadeveon Clowney work out.
Clowney, Bortles, Manziel and former Louisville quarterback Teddy Bridgewater have all met individually with the Texans more than once already.
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