Multiple media outlets reported that the five-time Pro Bowl selection sustained an Achilles injury while blocking for fellow wide receiver DeAndre Hopkins on a screen during the second half of Sunday's 32-30 loss to the Philadelphia Eagles.
The injury comes at a time in which the Texans (10-5) have answered a franchise-best nine-game winning streak with losses in two of their last three contests heading into a home tilt on Sunday (1 p.m. ET) against the Jacksonville Jaguars (5-10).
Thomas struggled through eight games with the Denver Broncos before being traded to the Texans on Oct. 30 for a fourth-round draft pick. The teams exchanged seventh-round picks as well.
The 31-year-old Thomas, who was the longest tenured member of the Broncos at the time of the trade, was second on the team in receptions (36) and receiving yards (402) and tied for the club lead in receiving touchdowns (three) this season.
Thomas had 20 receptions for 238 yards and two touchdowns during his time with Houston.
The 6-foot-3, 229-pound Thomas has collected 688 catches for 9,330 yards and 62 scores in 132 career games since being selected by the Broncos with the 22nd overall pick of the 2010 NFL Draft.
Houston promoted wide receiver Steven Mitchell from the practice squad to fill Thomas 'roster spot.