Tsitsipas out in Sydney, Struff comes through marathon day

Seppi struck a blow for experience over youth, coming from a set down to beat the promising Greek 4-6 6-4 6-4.

Veteran Italian Seppi claimed the only break of the second set and that decisive break in the third to lead 5-4, then showed no signs of nerves as he served out the match

Gilles Simon was pushed all the way as he ensured no other seeds would lose in Sydney, eventually prevailing 7-5 3-6 7-6 (7-3) against Australian John Millman.

There is one home favourite in the semi-final draw, though, as Alex De Minaur knocked out compatriot Jordan Thompson in straight sets.

Simon survives!No.4 seed @GillesSimon84 sets up a semifinal with Alex De Minaur after def. John Millman 7-5 3-6 7-6(3). #SydneyTennis pic.twitter.com/N3tD5RjR4o

— #SydneyTennis (@SydneyTennis) January 10, 2019

Diego Schwartzman will play Seppi on Friday after a 6-1 3-6 7-6 (7-1) win over Yoshihito Nishioka.

Meanwhile, Fabio Fognini and Pablo Carreno-Busta both fell by the way side in Auckland, with Kohlschreiber and Struff reaching a semi-final draw that contains no seeded players.

Kohlschreiber will play Tennys Sandgren after easing past second seed Fognini 6-3 6-1, but life was tougher for Struff, who endured a long day that included beating Carreno-Busta.

Struff was forced to go to three tiebreaks in a 7-6 (7-5) 6-7 (6-8) 7-6 (9-7) singles win in the last eight, while another two were required as he teamed up with Ben McLachlan in the doubles semis and defeated Wesley Koolhof and Marcus Daniell.