NYCFC leading scorer Heber was forced to exit his side's game against the Vancouver Whitecaps after 21 minutes, going down away from the ball and immediately signaling for a substitution.
Heading into the match against Vancouver, NYCFC were 11-2-3 when the Brazilian starts and just 2-3-5 when he's not in the starting XI.
Heber earlier gave NYCFC a 1-0 lead, a fine finish with the outside of his foot. It was his team-leading 14th goal of the season, which is good enough for 4th in MLS.
The first-year MLSer has been a revelation since his debut in April.
Following the game, Glenn Crooks reported that head coach Dome Torrent called the ailment a right quad injury, and while tests need to be taken, an initial timeline could mean somewhere around a month-long layoff for Heber.