NEW YORK: Marat Safin, relaxed about his impending retirement after a first-round loss at the US Open, had one final passionate Grand Slam message to deliver - quit picking on his little sister.

Safin defended women's world number one Dinara Safina on Wednesday, a day after she struggled past 18-year-old Australian Olivia Rogowska into the second round of the year's final major tournament.

"I have to protect my sister," he said. "The poor girl, she's trying her best. She's doing really well. She gets the attention, but not the kind of attention that a person deserves, especially when you're No. 1 in the world."

Safina has yet to win a Grand Slam title but has ascended to the throne in the WTA rankings and will remain there after the US Open even if Serena Williams defends her title for her third Slam crown of the year.

"Everybody is giving her hard time," Safin said. "Why is she No. 1? Is she a real No. 1 or not? She made eight double faults, 43 unforced errors. She struggled, almost lost to an 18-year-old.

"Who cares? I mean, she's No. 1 in the world. On this ranking, she's No. 1. Serena, even though she won two Grand Slams this year, she's No. 2.

"Sorry, but that's the way. Deal with that."

Acting every bit the big brother, 29-year-old Safin - six years older than Safina - made it clear he has had it with people diminishing 52-week ranking success in favor of two-week Slam success.

"They ask, 'Are you really No. 1 in the world?' Yes, she's really No. 1 in the world. Go check on the ranking. She didn't do the ranking," Safin said.

"Personally, I'm really like, I have to protect her. She deserves a little bit more than what she's getting right now. You can't imagine how crazy she is about sport. I don't think there is one person in the world more professional than her." Safin hit out at reporters for questioning Safina's credentials.

"Everybody is like hitting on her and giving her a hard time about this - what happened to this, what happened with that? Leave her alone," Safin said. "Give her a little bit less questions. Make her happy." Safin does not plan to stay and watch his sister try to claim her first Slam crown - "I really love my sister but I think she can manage without me" - and has little advice from his time atop the rankings for her now.

"She just needs to enjoy it while it lasts," he said. "It's difficult to be No. 1. There's too much attention, too much expectation from other people.

"Want it or not, you going to listen one way or another. Read newspapers, watch TV, everybody is talking about you basically. That sometimes is not easy. Sometimes people, they can be harsh on you.

"You need to really stay cold and do your thing and try not to pay attention to that and enjoy it. So it's pretty difficult, especially for women."