Fognini and his doubles partner, Simone Bolelli, had won their first two rounds when Fognini's default was announced.
"It doesn’t take 72 hours to do what they do. If they are investigating the situation, they should have not allowed him to play the match," Bopanna told Sportstar.
The Indian and his doubles partner, Pablo Cuevas, fell to the Italian team in the second round.
"If the tournament had already started to let him play doubles, they should have let him play the whole tournament and then made a decision," said Bopanna.
Bopanna also noted that the delay meant five players—the two teams who played the Italians and Bolelli—had been affected.
"Every player in the locker room knows it was wrongly done," he said. "Every player knows it was not the right thing to do."
Nadal also said the decision should have been made right away.
"If they want to suspend him, will be much better to do it immediately," he stated. "Not three days later or four days later, because then he was here playing for a few days."
The world No. 1 did not agree with suggestions that the delay was attributable to Fognini's comments needing translation from Italian.
"It takes four days for that translation? I don't think so," said Nadal.
Fognini could receive further fines and a suspension.
