Lee Keun-ho's impact off the bench against Russia was all part of the plan, according to South Korea coach Hong Myung-bo.
With the first half of Tuesday's game in Cuiaba ending scoreless, Hong waited just 11 minutes after half-time to throw Lee on up front in place of Park Chu-young and the Sangju Sangmu striker opened the scoring in the 68th minute.
Lee needed some luck to score with Russia goalkeeper Igor Akinfeev letting the 29-year-old's long-range shot slip through his hands and into the net but Hong claimed he always believed the forward could make an impact against the experienced Russian back four.
While South Korea have the fifth-youngest squad at the FIFA World Cup, Russia are in the top 10 for average age and started with a back four including three players in their 30s.
Speaking at his post-match press conference, Hong explained that he told Lee Russia's defenders 'would be tired and slowing down and he should prepare for that and be more aggressive'.
Although Russia's substitute striker Aleksandr Kerzhakov equalised six minutes later, Hong was pleased with the 1-1 draw to open South Korea's World Cup campaign.
"We didn't get the win but we can be happy with the draw," the 45-year-old said.
"It was our first match of the competition and opening matches are always difficult. Even so, I'm happy with what I saw.
"We studied Russia and their coach's tactics carefully and we prepared very well for the game. My players have given their very best and showed how good they are in both a tactical and physical sense."
South Korea's next match in Group H will be against Algeria in Porto Alegre on Sunday.