The Detroit Pistons are conducting their in-market bubble in the Motor City, but stars Derrick Rose and Blake Griffin aren't participating.

While speaking to Pistons reporters on Wednesday, head coach Dwane Casey explained why Rose and Griffin aren't in town, via Eric Woodyard of ESPN.

“All of our young guys are here. Derrick Rose and Blake are not here, which is totally understandable,” the Pistons tactician 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.”

Derrick Rose and Blake Griffin are the two best players on the Pistons and don't really need to take part in voluntary workouts. Both All-Stars have been training on their own, so they will be ready for whenever the 2020-21 season starts.

If the Pistons want to make the playoffs next season, Rose and Griffin have to stay healthy and play at a high level. Detroit won just 20 games in 2019-20 before the season was suspended in March due to COVID-19. They had the third-worst record in the Eastern Conference standings.

Rose was one of the few bright spots for the team during the season. He averaged 18.1 points, 2.4 rebounds and 5.6 assists in 50 appearances. The former MVP also shot 49.0 percent from the field, 30.6 percent from beyond the arc and 87.1 percent from the free-throw line.

Griffin, meanwhile, had a disastrous 2019-20 campaign after playing like a superstar in 2018-19. The former Los Angeles Clippers star underwent knee surgery after the 2019 playoffs ended and needed another procedure this campaign, which limited him to just 18 games. Griffin put up 15.5 points, 4.7 rebounds and 3.3 assists before going under the knife again.

The Pistons are hoping Griffin can regain his form and lead the franchise back to the postseason with the help of Rose.