Furious Australian Davis Cup captain Lleyton Hewitt has slammed a proposed shake-up of the competition as a "money-grabbing" exercise that will ruin the century-plus event.
The two-time Grand Slam champion said International Tennis Federation (ITF) president David Haggerty should resign if the plan fails to receive a two-thirds majority at the organisation's general meeting in August.
The ITF last month unveiled plans for a 25-year, US$3 billion partnership with investment group Kosmos, founded by Barcelona football star Gerard Pique, to revamp the current format.
It would see the Davis Cup reduced to a season-ending World Cup of Tennis Finals featuring 18 nations.
Currently, it is structured around a 16-nation World Group, contested over four weekends during the year. The remaining countries are then divided into three regional zones.
"There are a lot of people who are frustrated by it and see this as a money-grab. It is a money deal," Hewitt, his country's most successful Davis Cup player, told The Australian newspaper Friday.
"It is all about money, not representing your country. It makes absolutely no sense."
He vowed to do all he could to safeguard the competition, making clear he was "totally against" the changes.
"The (proposed) competition is not the Davis Cup. You can't call this the Davis Cup," he said.
"You can ask anyone for the past 50 years who has played the Davis Cup and (this proposal) is not what it is about, nor what it should be about."
The ITF is hoping the potential change will improve the appeal of the Davis Cup, which is often missing leading players, including Roger Federer and Rafael Nadal, because of scheduling concerns.
The investment will see significant increases in prize money to lure the sport's top stars, and provide more funding for grassroots tennis projects.
Each tie in the new event would consist of two singles and one doubles match over best-of-three sets, as opposed to the current four singles and one doubles match, each played over five sets.
Hewitt told the newspaper he was stunned not to be informed of the ITF's plans before the proposal was made public, and said Haggerty must go if the plan was rejected at the August meeting in Orlando.
"To me, I think Haggerty should lose his job if this does not go in his favour," he said.
"I don't think he can sit there and have those changes knocked back. I am quite strong on the whole thing. Tennis Australia is fighting against this."