Griffin twisted the knee in a scrimmage. The severity of the injury is unclear. The Clippers said he will have an MRI and be examined by doctors Thursday and then visit a specialist on Sunday.
Griffin injured the same knee in Game 5 of the Clippers' first-round series against the Memphis Grizzlies.
USA Basketball officials asked New Orleans Hornets rookie forward Anthony Davis, one of Team USA's final cuts last week, to report to training camp.
Davis was on his way to Las Vegas on Thursday afternoon after attending a cable TV event in Los Angeles on Wednesday night. USA Basketball managing director Jerry Colangelo told Y! Sports' Marc Spears that Davis will be available to play in Team USA's exhibition against the Dominican Republic, but Davis isn't guaranteed a roster spot if Griffin is unable to participate in the Olympics.
"I don't want to commit," Colangelo said. "That's as far as I want to go. Blake is gone and Anthony is here. That's as far as I want to go for the moment."
Colangelo said he was surprised that Griffin awoke with swelling in his knee.
"I saw him last night at the events. He didn't seem to be thinking about any discomfort, but he had some swelling this morning," Colangelo said. "I guess at the end of the season he had a little bit of an issue with this knee. Supposedly, he could've been scoped and chose not to at the time."
Griffin signed a five-year, $95 million contract extension with the Clippers this week.
Other popular content on Yahoo! Sports:
• Adrian Wojnarowski: Nets ink deal with Brook Lopez; Dwight Howard trade dies
• Steve Nash dons Lakers uniform for the first time
• Ray Allen, Rashard Lewis officially join Miami Heat
- Sports & Recreation
- Blake Griffin
- Los Angeles Clippers
- Team USA
- Los Angeles
- Memphis Grizzlies