Durant, who joined Phoenix in a blockbuster trade from Brooklyn last month, fell heavily as he drove for the basket ahead of the Suns' game against the Oklahoma City Thunder.
Video footage appeared to show Durant rolling his left ankle in the incident.
Shortly afterwards, the Suns confirmed the 34-year-old would miss the game due to "left ankle soreness."
Durant has made a dazzling start to his career with Phoenix in the three road games he has played for the club so far, averaging 26.7 points and 7.3 rebounds.