Westbrook announced last week that he tested positive for the coronavirus before the Rockets' departure, writing on social media July 13 that he was "feeling well" and quarantined.
Westbrook had to test negative for the coronavirus twice before being cleared to travel to the NBA's campus, according to the league's guidelines. He is required to quarantine in his hotel room for two days before being allowed to join the Rockets for practice and other team activities.
D'Antoni said that he anticipated that Westbrook, a nine-time All-Star who is in his first season with the Rockets, would be at full speed soon but probably not participate in Houston's scrimmage Friday.
"I do expect that once he clears everything that he'll be ready to go 5-on-5 and all that," D'Antoni said. "I would think Friday might be a little early. That'll be up to the medical staff and Russell himself and see how he feels in the days before. Hopefully, he'll get in a couple of scrimmages and then be ready for us to play."
NBA scoring leader James Harden arrived last week, five days after the Rockets' team flight, and cited "some family issues" as the reason for his delay. He has been a full participant in Rockets practices since clearing the NBA's quarantine protocol.
Once Westbrook is cleared to practice, the Rockets will have all of their regular rotation players available.
"Any time you miss a key piece like that, it makes it a little bit more difficult, but I know he'll be ready," D'Antoni said. "So on one side, we're just anxious to get him. It'll give everybody a little pep in their step, but there was no doubt before. The energy has been great. These guys have been practicing hard, so it's just one step closer to being whole. We can get him in there and work on a couple of things and get ready."