TOKYO, Aug 3 (Reuters) - Reigning champions the United States blitzed neighbours Canada 16-5 to storm into the semi-finals of the women"s Olympic water polo competition on Tuesday, keeping their bid for a third straight gold medal on track. The Americans will face the Russian Olympic Committee (ROC) team in the first semi-final at Tatsumi Water Polo Centre on Thursday. The ROC edged their quarter-final clash with Australia 9-8. European champions Spain beat China 11-7 to book their place in the final four, where they will meet Hungary, who beat the Netherlands 14-11 in the other quarter-final. The U.S., who have dominated women"s water polo in recent years, flew out of the blocks against Canada, effectively killing off the contest in the opening minutes. Captain Maggie Steffens, who broke the all-time Olympic scoring record in their last match, scored twice at the end of the first quarter to give the U.S. a 7-1 lead, which they extended to 11-3 by halftime. "It"s always great when you start out like that but you certainly can"t count on it," U.S. coach Adam Krikorian told reporters. "That got us feeling pretty confident and settled us into the game. "I think we could have played the third quarter much better. I thought we just let up a little bit. There"s a bigger goal here. I know we want to win, but we just want to play the right way... It"s just a frustrated coach talking." Steffens ended the game with three goals, as did Makenzie Fischer and Alys Williams, while goalkeeper Ashleigh Johnson saved 14 of the 17 shots she faced as the U.S. closed out the win in style. "Defence is what this game is all about," Steffens said. "Some days you"re going to score and some days you"re not but one thing you can control is your defensive effort. "Canada is a really good team... so for us to be able to shut them down early gave us a bit of that freedom on the offensive side."