The event, held Thursday through Sunday at the USA National Training Complex, had just one hiccup. Rain canceled the final day of action except for the championship game, which started more than three hours late.

Mater Dei of Santa Ana, Calif., capped off a tremendous tournament run with a 3-2 eight-inning win over neighboring Harvard-Westlake.

The Monarchs, coached by Burt Call, came into the tournament ranked 18th in the country by Baseball America. Now they can make a strong case to be No. 1.

They opened the tournament with a 10-3 win over Las Vegas Bishop Gorman, ranked No. 2 in the nation. They followed that with a 12-0 blasting of top-ranked Carroll of Corpus Christi, Texas. The semi-final win was a 5-1 decision over Sarasota High School of Florida.

Mater Dei fell behind 2-0 in the final. Ryan McMahon hit his second home run of the season in the fourth to cut the lead to 2-1. In the bottom of the seventh, junior Davis Tominaga hit a one-out homer to tie the score.

Ty Moore, an outfielder headed to UCLA, got on base on an error in the bottom of the eighth. He stole second, took third on an error and scored the winning run on a two-out, bases-loaded single to left by Ryan Barr. Moore was also the winning pitcher with four shutout innings in relief.

“We probably had three MVPs in the tournament,” Call said. “Moore and Tominaga for their offense and pitching and (junior catcher) Jeremy Martinez for the way he handled the games and his offense.”

Harvard-Westlake now hopes to get back injured right-hander Lucas Giolito. At one time, Giolito was projected to be the first high school righty taken in this year’s draft, and his teammate, Max Fried, could be the first left-handed prep pitcher to be chosen.

The tournament will feature some of the top teams and players in the nation next year. Rick Riccobono, director of development for USA Baseball, said he has 12 commitments for the 16-team field.

“I think we had a great experience for all the teams here,” he said. “I hope they got the experience they expected here and then some. I think we set the benchmark pretty high for next year.”