First, note the venue. This game is being played in Mexico City. That's a plus for Dallas, which is much closer to Mexico than Detroit. The Mavericks also have several Spanish speaking players, including star point guard Luka Doncic. 
The Mavericks have been dominant away from home going 15-3-1 ATS (83 percent) in their last 19 road games. Dallas is at least one level, if not two levels, higher than Detroit. The Mavericks last played on Sunday. So they've had ample time to rest, prepare and stew over their last game, a home loss to the Kings that ended a five-game win streak.
The Pistons have played a weaker schedule. They've met only three teams from the Western Conference, all of whom have losing records.