By A Staff Reporter: American Sebastian Korda reached the quarterfinals of a Grand Slam for the first time on Sunday after defeating Poland's Hubert Hurkaz 3-6, 6-3, 1-6, 7-6 at the Australian Open. After reaching to the quarterfinals he said, ' It is an extraordinary feeling. But I wasn't getting much energy during the fourth and fifth sets. I was trying to keep myself as calm as possible.'