Mayo pumped in 16 of his points in the fourth quarter, during which the Mavericks erased a nine-point deficit and outscored the Rockets 32-20 to win going away.
Mayo also pulled down eight rebounds and Chris Kaman provided 20 points with seven boards as the Mavericks logged an eighth straight win over their Texas rivals.
The Houston coach took the time off to deal with the unexpected death of his 23-year-old daughter Alexandra "Sasha" McHale, who died Nov. 24 after a battle with lupus.
Martin Bashir resigns from MSNBC over Sarah Palin comments
Exploding whale video goes viral on Internet