▁an ▁inv it ational ▁play off ▁to ▁ear n ▁one ▁of ▁the ▁American ▁wild ▁card ▁sp ots ▁in ▁the ▁main ▁draw ▁of ▁the ▁US ▁Open . ▁She ▁defeated ▁fellow ▁American ▁J ill ▁C ray bas ▁in ▁her ▁Grand ▁S lam ▁tournament ▁debut ▁to ▁become ▁the ▁young est ▁match ▁winner ▁at ▁the ▁event ▁in ▁six ▁years ▁at ▁the ▁age ▁of ▁ 1 6 . ▁Ke ys ▁also ▁won ▁an ▁inv it ational ▁play off ▁to ▁comp ete ▁at ▁the ▁ 2 0 1 2 ▁Australian ▁Open ▁but ▁was ▁unable ▁to ▁get ▁past ▁the ▁first ▁round . ▁▁ 2 0 1 3 : ▁R ising ▁star , ▁top ▁ 5 0 ▁debut , ▁top ▁ 1 0 ▁victory ▁Ke ys ▁began ▁the ▁year ▁ranked ▁No . ▁ 1 4 9 ▁in ▁the ▁world . ▁Having ▁made ▁it ▁to ▁relatively ▁few ▁W TA ▁main ▁draw s ▁in ▁previous ▁years , ▁Ke ys ▁played ▁only ▁tour - level ▁events ▁in ▁ 2 0 1 3 . ▁At ▁the ▁Sydney ▁International , ▁Ke ys ▁reached ▁the ▁quarter final s ▁of ▁a ▁W TA ▁event ▁for ▁the ▁first ▁time , ▁defe ating ▁Luc ie ▁Š af ář ová ▁and ▁Zh eng ▁J ie , ▁the ▁two ▁players ▁who ▁had ▁be aten ▁her ▁in ▁her ▁first ▁two ▁maj ors . ▁For ▁the ▁second ▁straight ▁year , ▁Ke ys ▁won ▁the ▁Australian ▁Open ▁wild ▁card ▁play off . ▁At ▁the ▁Australian ▁Open , ▁she ▁beat ▁Case y ▁D ella c qua ▁and ▁No . ▁ 3 0 ▁Tam ira ▁Pas zek