Rohtak, Jan 11: World youth championships gold medallist Shashi Chopra entered the fil of the featherweight category to set up a high-octane clash against Asian Championships silver medallist Sonia Lather at the 2nd Elite Womens Boxing Championship here on Thursday. Shashi had to toil to emerge triumphant as Sonia of Andhra Pradesh -- her opponent in the semi-fils -- had done her homework well and had answers to her strategy.