Dick Advocaat believes South Korea have a fighting chance of making the last 16 after storming back to defeat Togo.
The 2002 semi-finalists were stunned when the African nation, new at this level, took the lead through Mohamed Kader.
But the turning point came when their skipper Jean-Paul Abalo was sent off for two yellow cards.
South Korea took full advantage, and secured a 2-1 victory thanks to spectacular goals from Lee Chun Soo and substitute Ahn Jung Hwan.
Advocaat said: 'It is our first victory in the World Cup in Europe, and it is so important.
'If you win the first game you have a chance to stay in the tournament. If you lose, you make it difficult for yourself.
'You can see from the teams who won their first game what it means to them. The relief is evident.'
Advocaat changed to a more attacking formation in the second half, and it paid dividends.
He said: 'We were like two different sides. The team were nervous at the start, and so were Togo.
'But the players stayed calm at the break and it worked out for us in the end.
'We took a lot of risks and worked hard.
'It was fortunate to have worked out for us, but I think our luck was well deserved.'
Advocaat praised Ahn, saying: 'He made a difference, and I was pleased for him that he got on the scoresheet.'
Otto Pfister was back in the fold as Togo coach after walking out at the weekend in a row over unpaid bonuses.
He is expected to be in charge for their next game against Switzerland on June 19, but refused to comment on his long-term future.
Pfister was angry at the way his team went about their business.
He said: 'If you coach an African team, you have to respect your opponents. Everyone was over-confident, and we paid the price.'