Luka Doncic and Kyrie Irving proving Stan Van Gundy right. That’s how the Mavericks can win this year’s NBA championship over the Boston Celtics. The Mavs are one win away from setting up a Mavs-Celtics matchup in the NBA Finals as they lead the Timberwolves 3-1 in the Western Conference Finals.Doncic and Irving are playing at an elite level so far in the playoffs, so much so that Van Gundy said during a broadcast that Doncic and Irving are “the most talented backcourt in the history of the NBA.”That will be tested against a Celtics team that has options when it comes to throwing various defensive looks against the Mavs’ backcourt. The Celtics have four players capable of defending Doncic and Irving, starting with arguably the best perimeter defender in the game with Jrue Holida…