South Korea substitute Hwang Ui-jo claimed the only goal in a scrappy 1-0 win over regional rivals Australia in Busan on Friday. With both sides eliminated at the quarter-final stage of the Asian Cup in January, Friday's friendly was an opportunity to tinker with formations and personnel with the clock ticking down to the second round of 2022 World Cup qualifiers in September. The visitors, playing without several key regulars including Tom Rogic, Aaron Mooy and goalkeeper Mat Ryan, had the better of the first half and came closest to scoring when Mitchell Duke's flicked header from a corner struck the woodwork. The Koreans struggled to get anything going in the final third, frustrating the crowd of 53,000, and their only effort on goal came from Matthew Jurman when the Australia defender almost diverted Kim Min-jae's cross into his own net. However, Graham Arnold's side lost their way in the second half as South Korea upped the tempo and took control of midfield. With the home side cranking up the pressure, they got their reward in the 76th minute when Hong Chul's cross took the merest of deflections on its way into the box and Hwang stole in at the near post to glace the ball home. Australia goalkeeper Andrew Redmayne kept his side in the game five minutes later, getting down brilliantly to tip Son Heung-min's effort wide. Son, who only arrived in South Korea late on Tuesday after playing for Tottenham Hotspur in the Champions League final, delivered a typically energetic performance but found little space against a robust Australia defense. Next up for the Koreans is a friendly against Iran on Tuesday. Coach Paulo Bento was impressed with the way his side handled the new three-back system even though they looked awkward at times coming out of defense. "We used a new formation but our defensive players had a good game," he said, adding that it was good to have the option of going with three at the back for the upcoming World Cup qualifiers. Stand-in Socceroos skipper Aziz Behich was encouraged by their performance, saying there was "nothing but positives" to take from the game. "They should be proud of their performance because we played really well against one of the best in Asia," he told FOX Sports. — Reuters