MELBOURNE, Australia — Around the world, players, commentators and fans echoed the call of Roger Federer, who wants to know names of those suspected of match-fixing in a growing scandal that one ex-pro described as a “major wake-up call for the world of tennis.”

Many called for clarity, saying the public and players have a right to know who is suspected of cheating. Others warned that the match-fixing scandal has the potential to damage the reputation of tennis, just like doping or corruption scandals have hurt professional cycling, athletics, baseball and soccer.

Martina Navratilova, the 18-time Grand Slam champion, tweeted: “We need facts, not suppositions.”

The scandal broke Monday when the BBC and BuzzFeed News published reports — timed for the start of the Australian Open — alleging that tennis authorities have ignored widespread evidence of match-fixing involving 16 tennis players who have ranked in the top 50 over the past decade.

BuzzFeed titled its story, “The Tennis Racket,” and said that half of those 16, including a Grand Slam winner, were at this year’s Australian Open.

“This really casts a very dark shadow on our sport right now,” Mary Jo Fernandez said on ESPN, as part of a panel discussion Wednesday on the controversy.

“Hopefully because the world is watching, something will be done about it. We need to flag who these players were,” said Fernandez, a three-time Grand Slam finalist, winner of two Grand Slam women’s doubles titles and two Olympic gold medals.

Federer was among the first to demand more information: “I would love to hear names,” the Swiss star said Monday at a post-match news conference. Referring specifically to the claim about a former Grand Slam winner, he asked, “Was it the player? Was it the support team? Who was it? Was it before? Was it a doubles player, a singles player? Which Slam? It’s so all over the place. It’s nonsense to answer something that is pure speculation.”

His comments have resonated with those who say not knowing leads to dangerous speculation.

“This is turning into a witch hunt,” said Patrick McEnroe, a former French Open doubles champion and captain of the U.S. Davis Cup team who was in Melbourne commentating.

No. 1-ranked Novak Djokovic was put on the spot Wednesday at a post-match news conference, where a reporter told him an Italian newspaper had just reported that he “wanted to lose” a match in Paris in 2007.

“You can pick any match that you like that the top player lost, and just create a story out of it,” Djokovic said.

“This is now the main story in tennis, in the sports world, there’s going to be a lot of allegations,” he said, calling it “just speculation” and saying “it is not true.”

Until now, the average fan may have had little idea that tennis is one of the most gambled on sports in the world, with bookmakers actively taking bets mid-match. Between matches at the Australian Open, tennis experts have explained the mechanics of match-fixing, spelling out that it doesn’t necessarily mean throwing an entire match, but could involve taking money just to double-fault or lose a set.

“We in the tennis world have all heard the stories about this going on at the low levels. No one knew it was happening at the Grand Slams,” McEnroe said. “Where there’s smoke, there’s fire. This is a major, major wake-up call for the world of tennis.”

The BBC and BuzzFeed report prompted an immediate news conference by tennis’ governing bodies Monday in Melbourne Park, where representatives denied allegations that any evidence about match-fixing had been suppressed. Officials noted that the sport’s anti-corruption division, the Tennis Integrity Unit, has pursued 18 disciplinary cases that resulted in life bans from the sport for five players and one official. It was set up in 2008, after a surge of suspicious betting activity in tennis.

The problem for investigators, they said, is that match-fixing is very difficult to prove.

Many fans have also been shocked to learn that some of the sport’s top players have been approached and offered big money to throw matches.

Djokovic confirmed earlier in the week he was offered money to intentionally throw a match. The 10-time Grand Slam champion said that he was not directly approached but members of his support team were offered the money in Russia in 2007, an offer the player said was immediately rejected.

During a break in commentating for ESPN, Chris Evert said the scandal had deeply affected her.

“I have been so sad about this the last few days,” the 18-time Grand Slam winner said. “We as tennis players have always been so proud about the integrity of our sport.”

“Hopefully the truth will come out,” she said.

Andy Roddick thinks it will. The 2003 U.S. Open winner tweeted that he and another retired pro have been engaged in a guessing game: “Text I got from another former tour pro ‘we should see how many of the 16 betting guys we can name. I think I got at least 8-9.”

It’s bound to come out, Roddick said in another tweet: “In the age of leaks and social media, I don’t think secrets exist.”