SAN JOSE, Calif. (AP) Maria Sakkari of Greece upset third-seeded Venus Williams 6-4, 7-6 (2) on Friday night in the quarterfinals of the Mubadala Silicon Valley Classic.
Sakkari came back from 0-3 in the first set and 3-5 in the second set. She advanced to face American Danielle Collins – with the winner reaching her first WTA final.
Collins, a two-time NCAA champion for Virginia, advanced after former world No. 1 Victoria Azarenka of Belarus retired midway through the second set due to injury.
Azarenka led 4-2 in the first set before needing a tiebreaker to win the 72-minutes set 7-6 (4). She grabbed her right leg in the opening game of the second set, lost the first three games and was evaluated by a trainer and doctor before retiring prior to the fourth game.
Fifth-seeded Mihaela Buzarnescu of Romania secured the first semifinal spot by beating Australia’s Ajla Tomljanovic 6-1, 7-5. The Romanian will face No. 4 seed Elise Mertens.
Mertens, a Belgian, saved two set points in the first set, forced a tiebreak and won four straight games in the second set for a 7-6 (4), 6-3 victory over Johanna Konta. It’s Mertens’ fifth WTA semifinal of the year.
HALLE, Germany (AP) Alexander Zverev and Karen Khachanov bounced back from disappointments in Stuttgart last week to reach the second round of the Halle Open on Monday.
Second-seeded Zverev defeated Robin Haase 6-4, 7-5, while Khachanov celebrated his first match as a top-10 player with a 7-6 (5), 6-4 win over Serbia’s Miomir Kecmanovic.
Nine-time champion Roger Federer is the top seed at the grass-court tournament, a warm-up for Wimbledon. Federer is due to play Australia’s John Millman on Tuesday.
Both Zverev and Khachanov lost their opening matches in the Stuttgart Open. Zverev next faces American Steve Johnson, who defeated former champion Philipp Kohlschreiber 6-3, 6-3, while Khachanov awaits the winner between Jan-Lennard Struff and Laslo Djere.
STUTTGART, Germany — Matteo Berrettini beat Canadian teenager Felix Auger-Aliassime 6-4, 7-6 (11) to win the Stuttgart Open and his third tour-level title on Sunday.
The Italian saved five set points in a second-set tiebreaker and clinched his first title on grass. His other titles came at Budapest in April, and Gstaad, Switzerland, last year.
The 18-year-old Auger-Aliassime previously reached championship matches in Rio de Janeiro in February and the Lyon Open in May – both on clay.
Berrettini won all 50 of his service games during the week in Stuttgart. He did not face a break point against Auger-Aliassime.
Auger-Aliassime progressed to the final in his first professional grass tournament without playing Saturday as compatriot Milos Raonic withdrew ahead of their semifinal due to back problems.