DaMarcus Beasley’s goal in the third minute of stoppage time gave the United States a 2-1 win over South Korea in the Gold Cup Saturday afternoon at the Rose Bowl. Beasley scored with a left-footed rocket to the near post after Jeff Cunningham found the Fire midfielder free on the left side. Both American goals were scored by their teenagers. Landon Donovan, also 19, scored in the first half. “It wasn’t a pretty game today, for sure,” said U.S. coach Bruce Arena after the game. “Korea is a very difficult team to play against, they are very physical and very aggressive. I’m happy that there weren’t any rule requirements that you couldn’t play teenagers today, because we’d be in trouble if that were the case. It’s been such a long layoff for a number of players, it’s nice to get back on the field and start moving forward as a group. I’m pleased with the win today. Maybe a point would have been a fair result, but we’re going to take it.” The United States got an early scare when the Koreans were awarded a penalty for a foul by Dan Califf, but Yoo Sang Chul shot right at goalie Kasey Keller. Ante Razov sprung Donovan for the opening goal in the 35th minute. Donovan found himself all alone 25 yards out and lobbed the Korean keeper. South Korea equalized minutes later when Song Chong Gug beat Keller from 30 yards. The Koreans played the last 34 minutes with 10 men after Choi Jin Cheul was red carded for taking Donovan down. The makeshift American team created few chances against their future World Cup opponent, which had the support of thousands of Koreans residing in the Los Angeles area. South Korea severely tested the four-man backline that consisted of Jeff Agoos and Dan Califf in the middle and Frankie Hejduk and Carlos Bocanegra on the outside.