Son, 24, left the field in obvious pain in the 33rd minute of South Korea's 3-2 World Cup qualifying defeat to Qatar on Tuesday, clutching his right forearm after an aerial challenge.
The 24-year-old was representing South Korea in a World Cup qualifier against Qatar, but he failed to finish the match after landing awkwardly following an aerial challenge. "We only have a year until the Russia World Cup but that is enough time to build up a new team", he added. "The most important task for the next coach will be to boost the players' morale and building up a new team".
"Since Stielike became the head coach in 2014, he worked hard to develop South Korea's football environment, educate football instructors, while posting a good result at the Asian Cup (in 2015)", Lee said at a press conference at the NFC.
Months later, he led them to the Asian Cup final - without conceding a single goal en route - before they were beaten 2-1 by hosts Australia in Sydney.
South Korean media have already rolled out possible names for the next head coach, such as Huh Jung-moo, who previously led South Korea to the round of 16 at the 2010 FIFA World Cup, and Shin Tae-yong, who recently managed South Korea at the U-20 World Cup at home.
But trouble set in during Asia's final round of World Cup qualifiers, especially when they went down 1-0 to China in March-only their second loss to the Chinese in 32 games. It was South Korea's third defeat in the last five qualification games and left hopes of progressing to a ninth successive World Cup uncertain.
The loss in Doha leaves the Red Devils just one point ahead of Uzbekistan in second place in Group A of Asian qualifying with two matches remaining. South Korea play Iran and then Uzbekistan in their final two games.
In Asian qualifying, the top two teams from each of the two groups will advance automatically to the 2018 World Cup finals in Russian Federation.