Shin Tae-yong has congratulated Sweden on their 1-0 victory and admits that South Korea must quickly pick themselves up before facing Mexico.
The Asian side created just a couple of half-chances in their Group F opener and eventually came unstuck to a second-half penalty from Andreas Granqvist in Nizhny Novgorod.
South Korea now face a daunting task of overcoming Mexico and reigning world champions Germany if they are to reach the last 16, as they did in 2010, and Shin is taking positives from his side's slightly improved second-half display against Sweden.
"In the second half we made some adjustments to concentrate on our speed and managed to find opportunities, but Sweden played really well," he told reporters.
"Among the 32 teams at this World Cup, Sweden are one of the tallest. They are able to take advantage of this and their physical condition.
"We really wanted to win this match. It's unfortunate that we couldn't win today, but now our attitude is that we have to prepare ourselves very well for the match against Mexico. They are going to be a formidable opponent. We have to find our own way to face them."
South Korea had just two attempts against Sweden - Kim Shin-wook and Hwang Hee-chan failing to keep their headers on target in the second half.
