The match between Maria Sharapova and Timea Bacsinszky lasted an hour 42 minutes.
Swiss Bacsinszky reached the women's semis for the second time at Roland Garros, to meet Latvian teen Ostapenko.
The Tennis Integrity Unit (TIU) said that a match alert for a August 30 encounter at the US Open had been received from betting organisations.
Jiri Vesely defeated Lleyton Hewitt, who will retire after the Australian Open, 6-3, 6-7 (1), 6-4 before Karolina Pliskova came from 3-1 down in the second set to beat Jarmila Wolfe Gajdosova 7-5, 6-3 at Perth, Western Australia.
From Lucie Safarova and Madison Keys to Kevin Anderson and Vicktor Troicki, here are six underdogs to watch out for at Wimbledon.
Disillusioned with tennis, Timea Bacsinszky studied hotel management but was often told not to give up on her dreams. Now, she faces Serena Williams in the French Open semis.
Serena Williams is aware of Timea Bacsinszky's fighting abilities and says her French Open semi-final against her is hardly going to be a walk in the park.
Petra Kvitova won the first set but 23rd seed Timea Bacsinszky hit back hard to claim the next two.
Halep, the number one seed and third-ranked female player in the world, dispatched number eight seed Bacsinszky 6-2, 6-2 in 62 minutes in the $500,000 tournament to score her ninth WTA title.