DUBLIN—Theo Riddick and George Atkinson each ran for two scores and defensive end Stephon Tuitt returned a fumble 77 yards for another TD as Notre Dame routed Navy 50-10 in Saturday’s season opener in Ireland.A crowd of 49,000, mostly visiting Americans, filled Dublin’s Aviva Stadium for the first U.S. college game in Ireland since 1996, when the same two teams played in the Emerald Isle Classic.But this was no classic regardless of the enthusiasm of the fans, who did the wave even as both sides sent in substitutes in fourth-quarter garbage time.The Fighting Irish dominated the game, running the ball at will against Navy’s undersized defense and showing no signs of missing suspended starter Cierre Wood. Riddick went for 107 yards and Atkinson gained 99 on nine carries, leaving the Midshipmen and their outnumbered fans disconsolate at the end.Riddick started the Irish blowout with an 11-yard run to cap an 11-play opening drive. Atkinson broke free on the next drive, sweeping right and then cutting back and rampaging untouched through a bevy of Midshipmen for a 56-yard score.And sophomore quarterback Everett Golson, making his first start, put the Fighting Irish up 27-0 with a 5-yard jump ball into the end zone to tight end Tyler Eifert, who beat two smaller Navy defenders.Golson, who ended 12 of 18 for 144 yards, often looked best on play-action rollouts. But he did make one mistake that gave Navy some brief momentum when he tried to hit Eifert for a second TD and threw the ball into double coverage. Cornerback Parrish Gaines stepped in front of the pass at the Navy 4 for an easy interception.Navy appeared to be heading for its first touchdown on the ensuing drive, but backside pressure from Notre Dame defensive end Kapron Lewis-Moore spurred a clumsy fumble from Navy quarterback Trey Miller.Tuitt, listed at 6-feet-6 and 302 pounds, scooped up the ball and rumbled untouched 77 yards to put the Irish up 27-0 with barely 2 minutes left in the first half. It was Notre Dame’s longest fumble return in history.Navy managed a 26-yard field goal before halftime and opened the second half with a nifty three-pass drive capped by Shawn Lynch’s 25-yard grab to make it 27-10 but could get no closer.Atkinson and Riddick replied with two of Notre Dame’s three second-half touchdowns.Miller was 14 for 19 for 192 yards, but Navy’s triple-option managed only 149 yards rushing on 40 carries.Notre Dame’s defensive leader, inside linebacker Manti Te’o, recovered a fumble and intercepted Miller’s final pass of the day into triple coverage.One problem for Notre Dame: The Irish missed two extra points. The first attempt went wide right, while another snap went through the hands of holder Ben Turk.