Group Mblaq's member Lee Joon revealed his abs by ripping his shirt open.

'2011 MBC Gayo Daejaejun' took place on the 31st in Il San Dream Center. It was also broadcasted live in New York Timesquare, Im Jin Gak, Busan Bexco and others.

On this day, Lee Joon started his performance with piano as background music. Lee Joon went on to show off his intricate ballet moves, then ripped his shirt open, revealing his abs.

Mblaq performed the finishing act of part 1 of the music festival with the performance of their song 'Monalisa'.

Photo Credit: MBC Capture