Cerezo Osaka striker Forlan is one of a number of notable figures named by the International Consortium of Investigative Journalists as having been helped by the bank to dodge tax payments.
The report's file on Forlan says he joined HSBC in 2006 while playing for Villarreal and was connected to two client accounts that together listed four bank accounts, holding as much as $1.4 million in 2006-07.
Forlan did not respond to the investigation's initial request for comment, but subsequently released a statement via his own website.
"I want to clarify that my finances are, and have always been, in order, in a way that complies with all the tax laws of the different places in which I have worked, lived and have assets," he said.
"I affirm that I am not part of this alleged research and that my name was simply used as a 'hook' to be a public figure who is recognised worldwide."
Other sports personalities to be named in the report include Fernando Alonso, Flavio Briatore, Marat Safin and Valentino Rossi.
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