The Mavericks took a 2-1 lead in the series thanks to Vince Carter's three-pointer, which he levelled home right on the buzzer to give the Mavs a last-gasp victory.
"Both teams played well. It was a heck of a game," Popovich said after the encounter.
"Both teams made mistakes. Both teams did some things well. It came down to one shot. We made a shot, then they made a shot."
Game Four between the sides gets underway in Dallas on Monday.