The report by the Age newspaper in Melbourne, Australia, said that Hewitt was cautioned by chair umpire Fergus Murphy for unsportsmanlike conduct when he reacted angrily to being called several times for foot faults during a tough 6-7 (4-7), 6-3, 6-3, 6-7 (1-7), 6-2 victory against Robin Haase of Netherlands in a first-round match on Monday.
"I would doubt it," the Australian responded to a question at post-match news conference about whether Murphy was right to call his conduct unsportsmanlike.
"I'm not sure how many (foot faults) got called in the end (but) for some reason there's only one person that kept calling (them). We played two-and-a-half sets without that one person when they changed people, and then the same bloke came back again and I got done again," Hewitt said.
Hewitt beat Spain's Albert Montanes in straight sets in a second-round match Wednesday.