As Michael C. Wright of ESPN noted, a couple of teammates were forced to carry him off the court.
Tim Bontemps of the Washington Post added his thoughts:
Parker, 34, had 18 points in 25 minutes before coming out of the game.
When asked about the injury after the game, Spurs head coach Gregg Popovich told reporters "it's not good."
While the team is often cautious with its players during the regular season, the Spurs will need Parker back on the floor as soon as possible in order to help compete against the Rockets in the Round 2 playoff series.
After the veteran averaged 10.1 points and 4.5 assists per game during the regular season, he has stepped up his play in the postseason with an average of 15.6 PPG heading into Wednesday's battle.
Patty Mills, who has arguably become every bit as integral to the Spurs as Parker this season, will get a bump up in minutes if Parker misses any time.