How'd Andre Drummond feel when he saw LeBron James playing in an L.A. pickup game this week with Kevin Durant and Kawhi Leonard?
"I was mad I was not there!"
Drummond's also out in L.A. getting some offseason workouts in -- mostly at UCLA, where Bron and company got it in on Tuesday ... so he stopped by the TMZ office to hang out.
The Detroit Pistons superstar says he LOVES playing pickup hoop with other NBA stars -- especially those guys -- and he gave us the lowdown about what happens in those games.
Shocker ... Drummond says Kevin Durant dominates, telling us he's easily the #1 pickup player alive.
"He's very fun to watch and play with ... I think he's very unguardable."
Drummond also tells us why Kawhi Leonard is an absolute freak of nature -- just look at the size of his hands!
There's more ... Drummond also just dropped his new album, "Fyi" -- and says it solidifies his spot as the "best artist in basketball."