WINNIPEG, Manitoba — After the U.S. team’s final training session ahead of Monday night’s World Cup opener, Abby Wambach admitted she couldn’t wait to get started.

“The World Cup is here,” she said. “We waited for so long.”

And she’s already played in three of these tournaments. So imagine how excited Christen Press felt.

But Press was able to put the nerves and excitement aside long enough to score a huge second-half goal, snapping a tie and sending a shaky U.S. on to 3-1 win over Australia in the World Cup opener for both teams before a largely pro-U.S. crowd of 31,148 at Investors Group Field.

Megan Rapinoe had the other two American goals, one in each half. Alex Morgan, who hasn’t played since early April because of a bone bruise to her left knee, came on late in the second half for Sydney Leroux.

For the first hour Monday, it looked as if the U.S. would get off to an embarrassing start in group play, where it has lost just once in six previous World Cups. However, Press, among the most consistent scoring threats for the U.S. in the run-up to the World Cup, changed that in the 61st with a one-timer from 12 yards.

The play started with a goal kick from keeper Hope Solo — who had an excellent game — that found Rapinoe near midfield. Rapinoe sent the ball ahead to Leroux on the left flank, who dribbled to the edge of the penalty area before slipping a pass to Press in space.

And Press did the rest.

Seventeen minutes later Rapinoe put the finishing touches on the win. After collecting a pass from Carli Lloyd, she drove toward the penalty area before pulling up and shooting from the left edge of the 18-yard box. That shot hit nothing but the far side of the net to give the U.S. a two-goal cushion.

While the final score may look comfortable, though, the actual game was anything but, with a confident Australia challenging the U.S. at both ends.

With the Americans still trying to find their footing in the early minutes, Australia nearly stole an early lead when Emily Van Egmond latched onto a loose ball in the center of the 18-yard box and got off a blistering shot. But the ball went right at Solo, who used both hands to push it up and off the cross bar.

Seven minutes later Rapinoe gave the U.S. the lead.

Julie Johnston started that sequence by sending the ball ahead for Wambach, who then found Rapinoe well outside the penalty area. Rapinoe spun to elude Van Egmond and create space before sending a shot off the shin of Australian defender Laura Alleway and into the net.

Australia pulled back that goal in the 28th minute on a strong left-footed shot by Lisa De Vanna, the one player the American defenders said they feared most.

Michelle Heyman’s pass through the penalty area set up De Vanna, whose goal was her 34th in international play and sixth in a World Cup. Monday’s game also marked her 100th game with the Australian national team.

Wambach had two chances to give the U.S. back a lead before halftime. But a sliding attempt to deflect home a shot missed while her soft header in the 42nd minute died in the arms of Australian keeper Melissa Barbieri.

It then fell to Solo to protect the first-half tie, grabbing a free kick from Servet Uzunlar that skipped toward the post in the final minute of first-half regulation time.

Sweden, Nigeria tie

Nigerian forward Francisca Ordega scored with about three minutes left in the second half to give Nigeria a 3-3 tie with Sweden on Monday in Winnipeg, Manitoba, in both teams’ opening game of Group D play in the Women’s World Cup.

A tie is a good result for Nigeria, which is ranked 33rd in the latest FIFA rankings while Sweden is No. 5.

The game did not start well for Nigeria, as Nigerian forward Desire Oparanozie scored an own-goal 21 minutes into the game to give Sweden a 1-0 lead.

Sweden made it 2-0 when Swedish defender Nilla Fischer scored.

Forwards Ngozi Okobi and Asisat Oshoala scored goals three minutes apart to tie the game in the second half, before defender Linda Sembrant, who came on as a substitute, scored in the 60th minutes to put Sweden back on top by a goal. Ordega then scored late in the game forge a tie.

Nigeria had 14 shots compared with seven for Sweden, and the possession time was about equal.

NOTES: Alex Morgan, who scored two goals for the U.S. Women’s National Team in the 2011 World Cup, did not start Monday, as she continues to recover from a knee injury that has kept her off the field since early April. She entered in the 79th minute. …In an earlier game in Group D play, Nigeria, the 33rd-ranked team in the world, rallied from 2-0 and 3-1 deficits to force a 3-3 tie with Sweden, ranked fifth in FIFA’s points system. The United States will face off with Sweden on June 12 and Nigeria on June 16. …American forward Sydney LeRoux, who was born in Canada, made her World Cup debut in the starting lineup.

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