(Reuters) - Puerto Rico clinched a berth in the semi-finals of the World Baseball Classic with a 6-5 win over the United States in San Diego on Friday and remained unbeaten in this year's tournament.
Puerto Rico, runners-up to the Dominican Republic in the 2013 Classic, joined Japan and the Netherlands into the championship round leaving one spot available for the final games at Dodger Stadium in Los Angeles next week.
The last semi-final berth will go to the winner of Saturday's showdown between the U.S. (1-1) and the Dominican Republic (1-1).
The victory at Petco Park by Puerto Rico, 2-0 in second-round play and 5-0 overall in the tournament, dashed the long-shot hopes of Venezuela (0-2) advancing.
The U.S. team kept battling back throughout the game and threatened to erase Puerto Rico's lead in the ninth when Brandon Crawford's two-RBI triple cut the deficit to one and put the tying run at third base.
However, Seattle Mariners closer Edwin Diaz preserved the victory by striking out Josh Harrison.
Puerto Rico raced to an early 4-0 lead with singles from each of their first six batters off U.S. starter Marcus Stroman.
A throwing error by third baseman Nolan Arenado in the sixth inning gave Puerto Rico two runs, which they ended up needing to withstand the late U.S. rally.
Seth Lugo earned the victory for Puerto Rico for 5 2/3 innings of work in which he surrendered three runs and five hits.
Carlos Correa and Carlos Beltran each had two hits and a run batted in for the winners, while Buster Posey and Adam Jones homered for the United States.
Reporting by Larry Fine in New York; Editing by Sudipto Ganguly