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After a nearly two year absence from the lineup, it came as no surprise that Julie Ertz was once again starting for the U.S. women's national team in their Women's World Cup opener against Vietnam. Where she started in the USWNT's 3-0 win in New Zealand was a different story, though.

Ertz slotted into the team as a center back next to World Cup newcomer Naomi Girma, replacing Alana Cook after she started in the team's sendoff match against Wales. It called back to Ertz's tournament debut in 2015, when she won her first World Cup title as a defender, but the player has since made a name for herself as a defensive midfielder.

She still put out a strong performance against a Vietnam team that managed little going forward, and even had a chance to show off her attack-minded skillset with a passing accuracy of over 80% and 16 passes into the final third. The familiarity of the world stage, despite her positioning and lengthy absence through injury and maternity leave, helped.

"I feel like I'm at the point now where I'm like, 'Okay, I made it,'" Ertz told Fox Sports after the match. "I've been grinding to get back. I think you never take any World Cup for granted but when you're out there, it's go time and the only emotion I have is just grit and determination at this point."

Her experience as a two-time World Cup winner also helped a back line that featured two new players who made their tournament debuts in Girma and Emily Fox. It was the first time this group, plus left back Crystal Dunn, played together for the USWNT. It bolsters the camaraderie that the defensive unit feels, according to the left back.

"Having [Ertz] back there, her being such a veteran and leader, I think, is incredible," Dunn said, per Fox Sports. "She's leading that right side and I'm helping lead that left side obviously and I think she's so key for us. She's just ruthless."

For more coverage of the Women's World Cup be sure to tune into CBS Sports Golazo Network where Morning Footy, Box 2 Box and Attacking Third will be bringing you all the highlights, analysis and coverage you need of the action Down Under.

Lineup questions in the back

Head coach Vlatko Andonvoski played Ertz as a center back in what appeared to be a first-choice lineup when considering fitness, which naturally brings up the question, is this where the veteran will primarily contribute as the USWNT searches for an unprecedented three-peat?

Ertz filled the position well, as did the person who instead earned the defensive midfield role, Andi Sullivan. The Washington Spirit standout successfully quashed Vietnam's attacking efforts and swiftly rebooted the USWNT's attack, setting the tone for a successful outing for a midfield trio that also included captain Lindsey Horan and fellow World Cup newcomer Savannah DeMelo.

Andonovski will likely rotate through his squad before the group stage is over, so Cook may have a chance to earn a starting spot while Ertz could receive the opportunity to play further up the pitch. The team's upcoming match against the Netherlands will provide the US defenders with their first genuine test of the World Cup, and could begin to answer the question of how the USWNT line up as the tournament progresses.