Arena - his tactics paid off against Portugal (Allsport).

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United States coach Bruce Arena is likely to keep Frankie Hayduk in an unaccustomed left-back role for Monday's game against co-hosts and Group D leaders South Korea.

The Bayer Leverkusen defender switched flanks for the shock win against Portugal and fitted in well facing World Player of the Year Luis Figo.

And Hajduk promised he was willing to stay on the left for however long he was needed there.

"Being solid defensively as a team has been our main goal from the start, and taking it from there going forward," he said.

"In terms of being a left back, my main responsibility has been defensively, and all I have to worry about right now is keeping sharp defensively, and if we get a chance to go forward, I have (DaMarcus) Beasley in front of me."

"It wasn't the first time I'd played there in my life. But I haven't played there too often.

"But, being back there feels fine, like I said, it's not too much different on the right side.

"Your first responsibility is playing defence and defending your man and making sure he doesn't score or he doesn't get any crosses in.

"Just the difference is, you've got to be prepared to play with your left foot a little bit more.

"And in training, I've been working on that at every training, Bruce has wanted me to hit crosses, to make some passes with my left foot, which isn't too much of a problem for me, so it's really not too much of a difference."

Hajduk was also sure that getting the better of a side including the talents of Figo and Rui Costa could only help the Americans' confidence.

"Whenever you play against arguably two of the best players in the world and you hold them to a certain extent you feel proud of yourself after the game," he added.

"But, at the same time, that's what you're supposed to do, that's your job.

"They're great players, but when you step on the field, you believe you're a good player also.

"So, we welcome the challenge, and I think myself and Tony (Sanneh) and the whole defence and the whole team for that matter, stepped up to playing against such a major soccer power and it just kind of showed the world that, hey, we can play too."

And his coach agreed that the gamble paid off.

"He is a good one-on-one defender," he said. "And I thought for the game against Portugal we needed to have our best defenders out on the field."