HIGHLIGHTS-Tennis-Australian Open day nine

Highlights of Tuesday's ninth day of the Australian Open, the first Grand Slam tournament of the year (all times GMT): 0945 KVITOVA TOO GOOD FOR BARTY

Double Grand Slam champion Petra Kvitova blasted past local favourite Ashleigh Barty, winning 6-1 6-4 in 68 minutes to move into the semi-finals. READ MORE

Collins rallies past Pavlyuchenkova, into semis Greek Tsitsipas continues Melbourne quest

Djokovic passes Medvedev test to reach quarters Escape artist Nishikori beats Carreno Busta

Serena edges top seed Halep to reach last eight Learning never stops for Serena, 24 years on

Serena back to physical, emotional best: coach Simona Halep v Serena Williams - match stats

Evans made 'hash' of career, says Jamie Murray Tiafoe faces Nadal hoping to keep dream alive

FACTBOX-Frances Tiafoe v Rafa Nadal Australian Open order of play on Tuesday

0744 COLLINS RALLIES PAST PAVLYUCHENKOVA TO REACH SEMIS Danielle Collins dropped the opening set but rallied to beat Russia's Anastasia Pavlyuchenkova 2-6 7-5 6-1 and reach a Grand Slam semi-final for the first time in her career.

After surrendering the first set, Collins squandered a 5-2 lead in the next before levelling the contest, and the American switched gears in the decider to prevail in two hours and 16 minutes. 0501 TSITSIPAS OVERCOMES BAUTISTA AGUT

Stefanos Tsitsipas beat Spain's Roberto Bautista Agut 7-5 4-6 6-4 7-6(2) to reach his maiden Grand Slam semi-final. The 20-year-old also became the youngest man to make the last four of a Slam since Novak Djokovic at the 2007 U.S. Open. 0147 PLAY UNDERWAY ON ROD LAVER ARENA

Play began on the main showcourt at Melbourne on Tuesday, with 22nd seed Roberto Bautista Agut taking on Greek youngster Stefanos Tsitsipas in the quarter-finals. (Reporting by Shrivathsa Sridhar in Bengaluru)