Rockets head coach Mike D'Antoni said postgame that he expected Gordon to be out "a few days," but ESPN's Adrian Wojnarowski offered a more pessimistic outlook.
Shams Charania of The Athletic and Stadium confirmed Wednesday that Gordon is expected to miss two weeks.
Gordon landed on Vincent Poirier's foot after firing a pass to forward Robert Covington in the paint as time wound down in the first half:
Gordon apparently put weight on his ankle afterward but needed help off the floor. Postgame X-rays on the ankle were negative, per Wojnarowski.
The 31-year-old guard started and scored nine points on 3-of-8 shooting in 15 minutes. Ben McLemore replaced Gordon in the lineup and started for him in the second half.
Gordon has averaged 14.5 points on 37.0 percent shooting (31.9 percent from three-point range) during an injury-shortened season in which he has missed 30 contests because of knee and shin ailments.
Optimism reigned regarding Gordon in the run-up to the restart.
Gordon told reporters that he was good to go on July 1, per Kelly Iko of The Athletic: "I'm happy that I'm back to full health. Now I'm back to myself and what I should be doing."
He looked good during the Rockets' practice sessions leading up to the league's restart, with D'Antoni praising the ex-Indiana star on July 12.
"He hasn't missed a rep," D'Antoni said, per Jonathan Feigen of the Houston Chronicle. "Looks good. Shooting the ball extremely well."
Gordon shot just 8-of-24 (2-of-14 from three-point range) over his first two scrimmages, but he's been an integral part in Houston's success since arriving to town in 2016, averaging 16.5 points per game.
If Gordon is lost for any amount of time, McLemore would appear to be the top candidate to replace him in the starting lineup. The 27-year-old has averaged 9.8 points on 44.5 percent shooting in 63 games (19 starts) for Houston.
The Rockets could also turn toward Danuel House Jr., who has averaged 10.2 points on 42.7 percent shooting in 58 contests (47 starts).
Houston's first restart game will take place Friday at 9 p.m. ET against the Dallas Mavericks.