Dominic Thiem returns to competition at Buenos Aires but withdrawals have hit this week's other events.
Thiem has not played since retiring with illness in the second round of the Australian Open. His coach, Gunther Bresnik, would not specify what the illness was but said Thiem could slowly get back to playing events.
"From my point of view, he is fit to play a match again," the Austrian's coach told APA. "Yesterday and today, he was good in practice, [but also] he has done little or nothing for several weeks."
Thiem, ranked No. 8, is the top seed at Buenos Aires but this week's other two ATP tournaments both saw their highest-ranked names withdraw. Kevin Anderson, the defending champion in New York, will not be playing because of an elbow injury.
Frances Tiafoe has been given a wildcard at New York, which is now led by No. 9 John Isner.
Alex de Minaur and Jack Sock have also withdrawn from the event.
Rotterdam, where top seed Alexander Zverev had previously withdrawn with an ankle injury, also announced that third seed Marin Cilic will not be playing. No. 7 Kei Nishikori will be the highest-ranked player at the ATP 500 event.
The tournament has also experienced withdrawals from Grigor Dimitrov, Kyle Edmund and Nick Kyrgios.
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