The New Zealand side, ranked 16th in the world, went behind in the 10th minute and faced a 2-0 half time deficit after their 17th ranked opponents struck seven minutes before half time.
The second half produced two more goals for the South Korean side as they scored eight minutes after the restart before adding a fourth in the 72nd minute.
Tuesday’s defeat is the biggest suffered by Tony Readings’ team since the Football Ferns were beaten 5-0 by Mexico at the 2011 Cyprus Cup event.
Readings says the windy conditions played a role in the outcome but his side conceded goals to quick counter attacks from their opponents.
“In the first half while we played with the wind and whilst we kept the ball for the majority of the half, we got caught on the counter on two occasions,” Readings said. “They had two chances in the first half and, to be fair to them, they’ve put them away.
“We’ve come in at half time without playing too badly but without playing up to our best level.
“In the second half we played into a really strong wind. We didn’t start as well as we could have then we’ve got on top and been caught again on the counter.
“It’s difficult to accept losing 4-0 but what we’ve succumbed to is a little bit of indecision at the back and that stems back to a lack of cohesion from having new players in there.
“What we’re really proud of is the way the players kept fighting right to the very end, pressing forward and trying to get a bit more respectability back into the game and that bodes really well.
“We know we’ve got got ability and quality in the team and if we can combine that with the attitude and commitment the players showed today we’ll come back even stronger.”
Readings handed CJ Bott and Evie Millynn their first senior international caps with both players appearing as second half substitutes.
“What we’ve been able to do in this tournament is give a lot more game time to younger players. While last year we got some really great results, we did that without building too much depth in the squad.
“What we’ve got to do when we get the World Cup and Olympics is have a squad where you’ve got two quality players in each position so you can deal with injuries and rest players and rotate them.”
“Individually players are performing well but it does take a while for the players to gel when they first come into the team and that’s cost us a little bit in this tournament.”
The Football Ferns finish up the Cyprus Cup tournament with Thursday morning’s 11th place play-off match against Finland.
Cyprus Cup 2014 – Group C
New Zealand 0
South Korea 4 (10’, 38’, 53’, 72’)
Halftime: 0-2
New Zealand: 1. Erin Nayler (GK), 4. Katie Hoyle, 5. Abby Erceg (capt), 6. Rebekah Stott, 9. Amber Hearn (13. Rosie White 65’), 12. Betsy Hassett (11. Kirsty Yallop 60’), 15. Meikayla Moore (3. CJ Bott 82’), 16. Annalie Longo (19. Evie Millynn 85’), 17. Hannah Wilkinson (25. Stephanie Skilton 75’), 18. Katie Bowen, 20. Helen Collins.
Substitutes not used: 10. Sarah Gregorius, 21. Lily Alfeld (GK), 26. Megan Lee
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