Melbourne, Jan 28 (IANS): World No.35 Madison Keys battled past veteran Venus Williams in three tough sets 6-3, 4-6, 6-4 to reach the first Grand Slam semifinal of her blossoming tennis career at the Australian Open here Wednesday.

Keys came out firing from the beginning, storming through the first set, 6-3, but she lost her way in the second set, falling behind 1-4 at the Melbourne Park.

She clawed back to 4-all but Venus found rhythm from there, winning five of the next six games to take the second set and build a 3-1 lead in the third.

But Keys reeled off the last three games of the match to seal a spot in her maiden Grand Slam semi-final.

"First of all, I'm very happy I'm into the semi-finals, but the moment's definitely sweeter being able to play Venus to get there," said Keys, who idolised the former No.1 when she was growing up.

"I was trying to enjoy the moment, and I did, and I get to enjoy another moment in the next round!"