The marquee match between Leander Paes and Mahesh Bhupathi with their respective doubles partners has been pushed to Saturday.
The doubles schedule was thrown into disarray when Germany's Denis Gremelmayr pulled out of the tournament on Thursday with an injury in the right-hip and Juan Martin del Porto retired due to illness.
The winner of the quarter-final between Bhupathi-Mario Ancic and Paes-Aisam Qureshi, who were slated to meet Gremelmayr and compatriot Simon Greul, will thus receive a walkover into the final.
Potro, who upset Carlos Moya in the singles first round, took ill during his match against Ramon Delgado and had to withdraw from the doubles (with Juan Monaco), scheduled the same day.
The other semi-final will be between India's Rohan Bopanna-Mustafa Ghouse and Great Britain's Jamie Delgado and James Auckland, who benefited from Potro's withdrawal.