South Korea reached the knockout stage as runners-up in Group A with two wins and one loss, while Portugal were the No. 2 team from Group C with one win, one draw and one loss. 

Shin's players were looking to repeat South Korea's U-20 World Cup success in 1983 when the country reached the semifinals in Mexico. Also, with the latest loss, South Korea failed to end the winless drought against Portugal at the U-20 level, falling to three draws and five losses.

Against the two-time tournament champions, South Korea gave up the lead in just 10 minutes when Bruno Xadas poked home Yuri Ribeiro's cross. The visitors doubled the lead in the 27th when Bruno Costa's right footed strike beat goalkeeper Song Bum-keun.

"Today, we lost because we gave up two goals in counterattacks in the first half," Shin said. "When you are on a lucky day, the ball doesn't end up on the opponent's path after taking a deflection off our defenders, but today, Portugal had their lucky day."

Shin has never used the same formation twice at the start of a match in this tournament. He used a 4-3-3 formation in South Korea's 3-0 win against Guinea, and came up with a 3-4-3 formation to overcome Argentina 2-1. He then deployed a 3-5-2 formation against, but fell to England 1-0.

Against Portugal, Shin's team started with a 4-4-2 formation with Cho Young-wook and Ha Seung-un playing up front, but it turned out to be a failure.

"Portugal must have expected us to come up with a 4-3-3 formation," he said. "I thought it'd be better for Cho to work with Ha up front when penetrating Portugal's defensive line and that's why I used the 4-4-2."

Shin said he wasn't thinking about playing defensively in the knockout stage.

"We were playing at home, and for our football fans, I really wanted to win, and so did our players," he said. "You can play defensively and collect a win, but I thought it'd be better for us to beat Portugal with attacking football because that will develop South Korean football."

Shin said, overall, he was pleased with how his players performed in this tournament, but in order to make further progress, the 46-year-old coach emphasized that they need to play regularly at a high level.

"If you look at our opponents' squads, most of their players are with professional football clubs," he said. "I realized that if we want to produce positive results in the future, more players need to play in the pro leagues."

On the bright side, Shin's team saw two FC Barcelona prospects -- Lee Seung-woo and Paik Seung-ho -- showing their caliber at the U-20 World Cup, although both of them stayed silent against Portugal.

Shin said both also need to play on a regular basis with their clubs if they want to become bigger players. Lee is currently with FC Barcelona Juvenil A, while Paik is with the Catalan club's B team.

"Both are playing with the youth team of the world's top club, but they need to play matches," he said. "Both players have potential, but I think if they want to grow, they should consider finding a team where they can play regularly." (Yonhap)