Wednesday’s ESPN doubleheader closes with what could be the NBA’s next great rivalry. Cooper Flagg and the Mavericks visit Victor Wembanyama and the Western Conference champion Spurs at 9:30 p.m. ET, and it’s the second time these two Texas teams have met in less than two weeks. Fanatics Sportsbook is offering new users promo code FOXNEWS350 to bet $20 and get $350 in FanCash on Mavericks vs. Spurs.The Flagg vs. Wembanyama story started badly for Dallas. In Flagg’s NBA debut in October 2025, Wembanyama put up 40 points and 15 rebounds in a 125-92 blowout. By the end of the season, Flagg was holding his own, trading baskets with the 7-foot-4 Frenchman and finishing at the rim over him. Flagg went on to win Rookie of the Year. Wembanyama led San Antonio to 61 wins and a trip to the NBA Finals.That gap between the two teams hasn’t closed yet. When they met on Oct. 24 in Dallas, the Spurs were double-digit favorites with Flagg sitting out, and the Dallas frontcourt was already thin.The Spurs have one of the deepest young cores in basketball. De’Aaron Fox runs the offense, Dylan Harper and Stephon Castle give them two more guards who can create, and Wembanyama spent the offseason sharpening his post game. When the offense runs through him on the block, there’s no one on the Mavericks’ roster built to stop it.The bigger issue for Dallas is on the glass. If the Mavericks’ bigs are limited again, Wembanyama will have his way on the boards at both ends.The Mavericks need Flagg on the floor and aggressive. He’s taking on a much bigger role in Year 2, and with Kyrie Irving back in the backcourt, Dallas has enough shot creation to hang around if it can stay out of foul trouble against San Antonio’s size. Keeping Wembanyama off the offensive glass is the whole game plan.This is the cleanest angle in the game. Dallas’ frontcourt has been depleted, and the last time these teams met, the Mavericks were already shorthanded inside. Wembanyama’s length makes him a nightly double-double threat, and against a team that struggles to box out bigs, his rebounding line is the bet. Put $20 on it and collect $350 in FanCash once it’s graded, win or lose.The night opens with 76ers at Pistons on ESPN at 7 p.m. ET, and Cavaliers at Thunder tips at 8 p.m. ET. Lakers at Kings and Heat at Clippers close out the West Coast window.The NBA’s next great rivalry on national TV, with Wembanyama and the Spurs looking to keep their grip on the series. New users can bet $20 on Mavericks vs. Spurs and get $350 in FanCash with Fanatics Sportsbook promo code FOXNEWS350.