James Madison has risen to No. 22 by pulling off two miraculous wins in hostile arenas and by rallying in the final minutes for a clutch victory at home.Now it’s time for James Madison (4-0) to be tested in a completely different environment as it faces Southern Illinois (3-0) in the Cancun Challenge on Tuesday in Cancun, Mexico.Coming off a thrilling win in an electric arena at home, 76-73 over Radford, how will the Dukes fare in a tropical location, where the atmosphere will be breezy and the clamor in the gym will be muted?”We’re not winning that game without our crowd. They just lifted us up,” James Madison coach Mark Byington said on Friday night after his team outscored Radford 6-0 in the final 3:35.The Dukes got stops on the Highlanders’ final six possessions, including a key steal by defensive stopper Xavier Brown with 9 seconds left. It was Brown’s third of the game in his 11 scrappy minutes on the floor.”I love to stop people,” Brown said. “I love to see the frustration in somebody’s face when they can’t get to where they want to or to score.”Terrence Edwards Jr. (21 points, seven rebounds), T.J. Bickerstaff (20 points, eight rebounds) and Julien Wooden (15 points) supplied the offensive firepower as the Dukes protected their first ranking in program history.With the sudden national acclaim that came after their 79-76 overtime upset of then-No. 4 Michigan State on opening night, the Dukes have continued to be at their best at the end of games.In halting Kent State’s 23-game home winning streak in two overtimes, 113-108, James Madison needed five points in the final 3.8 seconds of regulation from Noah Freidel to shock the Golden Flashes.”We’re kind of finding out who rises to the top at the end of games. It seems to be everybody,” Brown said.Southern Illinois arrives in Cancun riding a quick start with three decisive wins, though it has yet to play a team rated better than No. 250 on KenPom.com.