Durant has been out since straining his calf in Golden State's Game 5 win over the Houston Rockets in the Western Conference semi-finals.
The Warriors went on to close out Houston in six games before sweeping the Portland Trail Blazers in the Western Conference Finals.
Durant was having a stellar postseason before the injury. He averaged 34.2 points and 5.2 rebounds while shooting 51.3 per cent from the field in 11 playoff games.
And Kerr confirmed that two-time NBA Finals MVP Durant will not be fit to play Thursday's opener.
— OptaLarry (@OptaLarry) May 24, 2019
Meanwhile, Cousins tore his left quadriceps muscle during the Warriors' first-round series in mid-April and Kerr confirmed he is closer to a return than Durant.
Cousins signed a one-year, $5.3million deal with the Warriors in July and missed the team's first 45 games as he continued to recover from a torn Achilles.
He finished the regular season averaging 16.3 points and 8.2 rebounds in 25.7 minutes per appearance.
Photo Getty Images. Caption: Kevin Durant of the Golden State Warriors