India suffered a shocking 4-6 defeat against Korea in their opening match of the Under-21 Sultan of Johor Cup hockey tournament. At Johor Bahru in Malaysia today, India were leading four-nil at the breather. But a valiant Korea pumped in as many as half a dozen goals in the second half to dash India's hopes at the Taman Daya stadium. Korean captain Yang Ji Hun recorded a superb hat-trick to script a remarkable come-from-behind victory. India will face fromidable Australia in their next round robin league match tomorrow, while Korea will take on Pakistan.