Bayless also dished off four assists and perpetrated four steals for Memphis, seeded fourth in the Western Conference.
Ed Davis helped out with 11 points and 11 rebounds for the victors.
The Mavericks, meanwhile, fell for just the second time in six games despite 26 points from Dirk Nowitzki.
Pistorius testifies he didn't consciously pull trigger when he shot girlfriend
Charlize Theron not engaged to Sean Penn 'yet'