Do not be fooled by Megan Rapinoe's smile.

You will likely be tempted. The 29-year-old is a dynamic mix of suave modernity and old-school rebelliousness, honed by a playing career that has taken her to club teams in Australia, France, and four American cities.

But beneath the northern California native's wavy crop of bleached-blond hair, there is a will of steel - and it came to the fore Monday night in the United States' World Cup-opening 3-1 win over Australia.

Rapinoe scored two goals as the Americans vaulted to the top of the Group D standings.

The first tally started with a spectacular spin move on top of the ball while she was surrounded by an array of blue-clad Australians. That created just enough space for her to sprint forward, set the ball on her right foot, and hit a 20-yard shot that deflected in off Matildas defender Laura Alleway.

The second was a seemingly effortless run down more than half the field along the left side, culminating in a low shot from 15 yards out.

"I was doing my best [Lionel] Messi impression," Rapinoe said, referring to the Barcelona and Argentina wizard. "A much slower version of him."

Throughout the night, Rapinoe was not afraid to take aim at Australian goalkeeper Melissa Barbieri.

"I probably shoot too much," she quipped. "It doesn't matter what kind of shot it is for me, I'll take it."

For all of the attacking stars that the U.S. team has, none brings the element of surprise that Rapinoe does. And she does so from a crucial position as a wide midfielder, which helps the Americans stretch out opposing defenses.

"She's unpredictable out there," fellow midfielder Carli Lloyd said, "and helps tremendously, I think, just kind of unbalancing teams."

Rapinoe also has a knack for delivering in the clutch. Her second goal provided much-needed insurance and allowed a U.S. team that had been nervous all night to finally loosen up.

That was not lost on coach Jill Ellis.

"Megan thrives in these big games, these big moments," Ellis said. "She's got ice running in her veins, but a lot of passion inside of her, and she's a game-changer. That's what makes her special."

Sweden certainly will not overlook Rapinoe in a group stage showdown Friday night at Winnipeg Stadium. Coach Pia Sundhage, who led the United States from 2008 to 2012 and helped Rapinoe's career blossom, will see to that.

But if the Swedes let their guard down for a moment, Rapinoe will surely pounce. Just ask those Australian defenders who thought they had her cornered, only to find themselves grasping at air as she spun and raced away.