If the swashbuckling efforts in the first 20 minutes provided a glimpse of the United States women's national team's future , then the arrival of Abby Wambach at halftime supplied a reminder of the lingering utility of the more established ways.

Wambach - in tandem with returning goalkeeper Hope Solo - served as the cavalry for an American side in need of alternatives. Korea Republic settled well after the Americans scored twice in the opening seven minutes and started to assert more control over the game.

As the first half progressed, the United States lacked the precision and the tempo mustered in the opening stages and struggled to devise a way to alter the emerging calculus with its work in possession and through the channels. Cho Sohyun's well-taken goal after 27 minutes even placed the Koreans in position to perhaps snatch a second half result.

United States coach Tom Sermanni implored his players to buckle down at halftime and sent Wambach onto the field to lead the way to the eventual 4-1 victory at Gillette Stadium.

"I thought we were really dynamic in the first 20 minutes and, yeah, it died off a bit," Wambach said. "But, for me, when I come on, I want the ball in the box as much as I can, especially against South Korea. We need to test them in the air. We need to test them on our crosses to see what they can do on crosses into the box."

Wambach functions as a prototypical target forward from the moment she steps onto the field. She possesses ample technical ability with the ball at her feet, but her physical attributes occupy her markers and present pervasive problems for opposing defenses as they attempt to compensate. Other teams simply cannot cope with her when she puts herself about and slides into the right spaces. And her work in leading the line creates more operating room for her teammates and lays the foundation for intricate passing moves behind her.

"It's not just her aerial presence: it's her presence," Sermanni said. "Having that target in there, that sort of presence, is really, really important. It helps all of the other players because it takes the pressure off all of the other players as well. She's still a world class player, undoubtedly, and a very, very potent player."

Wambach's potency stems from a steady diet of service into the penalty area. Her strengths naturally prompt the United States o eschew much of its combination play through midfield and turn toward a reliance on crosses and diagonals to use Wambach to her fullest effect.

These tweaks work particularly well against a team like Korea Republic that lacks the personnel to adequately cope with Wambach. The veteran striker imposed her will on the game and threatened constantly with Heather O'Reilly and Christine Rampone maintaining the necessary supply lines.

On another night, Wambach might have scored two or three and paved the way for Alex Morgan to grab another. Several half chances went begging as she threw herself about inside the penalty area. Her best opportunity from the run of play ended in frustration after Kim Jungmi somehow kept a trademark header from an inviting O'Reilly cross inside the final quarter of an hour.

Morgan eventually paved the way for Wambach's 156th international goal (two behind Mia Hamm's record total of 158) by procuring an impudent challenge and a subsequent penalty kick award in second half stoppage time. Wambach accepted the responsibility from 12 yards and thumped home into the right corner to round off her ample second-half contribution.

"I'm glad to have gotten the penalty kick," Wambach said. "I probably deserved one earlier, but that's the way it goes sometimes. Heather O'Reilly and Christine Rampone, they were sending some great service into the box. I feel a little unfortunate that I couldn't get at least one of them."

Although another goal or two would have aided Wambach in her quest to catch and surpass Hamm, the 33-year-old's overall display offered a reminder of her effectiveness and her necessity to this side during this evolutionary period.

Sermanni will guide this team through a natural progression over the next few years as he attempts to build an outfit capable of claiming the World Cup in 2015 and defending its Olympic title in 2016. The process will naturally involve some changes to the current setup and an increased reliance on possession through midfield, but this match - and Wambach's continued production - reinforced the importance maintaining the links to the more direct past and using them to facilitate and support the arrival of a new era.