Washington - Australian top seed Samantha Stosur, defending Washington Open champion Sloane Stephens and German teen star Alexander Zverev are setting aside Zika virus fears to compete at the Rio Olympics.
But Sam Querrey, who upset world number one Novak Djokovic at Wimbledon, isn't going to Brazil because it just isn't that big a deal to him.
Differing views over the mosquito-carried Zika virus and the rash of recent tennis withdrawals from Rio came out Monday on day one of the ATP and WTA event, the first hardcourt stop on the path to the US Open.
"It's not something you want to take lightly," Stosur said after beating Russian qualifier Alla Kudryavtseva 6-3, 6-0.
"Other people say there are going to be far worse things going on than Zika. It's about being smart, following all the guidelines. I've had all the vaccinations. It certainly has entered my mind this time around."
Several top NBA players, more than 20 men's golfers and several top tennis players have withdrawn from Rio, many but not all citing the potential for contracting Zika, which causes severe illness and has been linked to birth defects.
"I'm kind of scared but I'm not having any kids any time soon so I should be OK," said Stephens, a 23-year-old American set to make her Olympic debut. "Some people are way more sensitive and some people aren't. It just depends on the person."
Canada's seventh-ranked Milos Raonic, who lost the Wimbledon men's final to Britain's Andy Murray earlier in July, eighth-ranked Czech Tomas Berdych and Austria's ninth-rated Dominic Thiem all said no to Rio.
So did 16th-ranked John Isner, the Washington men's top seed, and Querrey, who doesn't see tennis or golf as true Olympic sports.
"For tennis and golf, the Olympics isn't a top priority," he said. "We have four other Grand Slams. Those are the main focus.
"Some sports in the Olympics, (tennis) and golf, I feel like maybe shouldn't be in there. It just wasn't a priority of mine at all."
That's a stark contrast to 19-year-old Zverev, who at 27th in the world has become the youngest man to crack the top 30 since Djokovic in 2006.
And Zverev has even suffered severe illness after a bug bite.
"I was at the US Open and something bit me," Zverev said. "I'm going to be very careful because of that. I only won one match the rest of the year. My leg got a lot swollen. I was really sick with fever, lost a lot of weight, couldn't eat.
"You think about it, that's quite a serious thing. You don't want to get something but the Olympics is a very big event.
"I'm a little bit worried about the Zika virus. A lot of people have pulled out. But it's going to be a lot of fun."
Isner has a first-round bye and a round-two date with Australian qualifier James Duckworth, who ousted American Tim Smyczek 7-5, 6-1.
Aussie John Millman, Rio bound as well after Olympic pullouts by Nick Kyrgios and Bernard Tomic, advanced to a second-round match with Cypriot Marcus Bagjdatis by downing American Denis Kudla 7-5, 6-0.