Phase 1 of the NBA in-market bubble has started for the Detroit Pistons, but veterans Blake Griffin and Derrick Rose, and free agents Christian Wood and Langston Galloway aren't participating right now, according to coach Dwane Casey.

"All of our young guys are here. Derrick Rose and Blake are not here, which is totally understandable," Casey said. "Both are working out, and it's nothing physical. They're both 100 percent. Blake's working out in LA, and Derrick is in and out of town."

Casey has been in contact with both Wood and Galloway throughout the process and also called it "totally understandable" that they're not attending, since they're free agents.

"We're not reading anything into that either way," Casey said. "So it's just something I totally get because if I'm a free agent, I wouldn't attend anyway to the team you're not under contract with."

The Pistons currently have 15 players in attendance, including five G League players, to rotate three teams. Most of the work this week is one-on-one.

Next week will be Phase 2 from Sept. 21 to Oct. 6, with a lot of 5-on-5 action and group training activities for each of the eight NBA teams that didn't participate in the Orlando, Florida, restart.

Participation for players in both individual and group workouts are voluntary, but they must remain on the campus-like environment.

Detroit will pick seventh overall in the 2020 NBA draft on Nov. 18. Casey and new general manager Troy Weaver are working to bring relevance back into Motown, even with the nontraditional methods of evaluating talent in the midst of the coronavirus pandemic.

"We're not really rebuilding here in Detroit," Casey said. "I think our basketball fans deserve a lot, so we like to use the word retooling, restoring as much as rebuilding. So, again, it doesn't have to take a long time because if our young guys are making the progress we expect them to make, it shouldn't be a long-term restoring. And again, if we get the opportunity to get the right free agent that's out there."