Complex sentence: Li's victory at the former event made her the first and only grand slam singles champion from Asia; she had already become the first player representing Asia to appear in a grand slam singles final, at the 2011 Australian Open.
Split into simpler sentences: Li's victory at the former event made her the first and only grand slam singles champion from an Asian country. Prior to this, Li had already become the first player representing Asia to appear in a grand slam singles final, a milestone she achieved at the 2011 Australian Open.