Three-time gold medalist Venus Williams has the ranking she needs to become a four-time Olympian.

Williams climbed to 47th Monday in the WTA rankings, which determine who qualifies for the Olympics. The top 56 singles players are automatically accepted, with a maximum of four per country, and Williams is third among U.S. women behind her sister Serena (fifth overall) and Christina McHale (29th).

The fourth American in women's singles is expected to be Varvara Lepchenko, an Uzbekistan native who became a U.S. citizen in September. She's ranked 52nd to edge out Sloane Stephens, ranked 57th, and Vania King, ranked 59th. Because of injuries and players declining to take part, the cutoff for making the Olympics has traditionally been in the high 60s.

McHale and Lepchenko would be first-time Olympians.

The USTA now awaits official invitations for its top players from the ITF. The ITF has yet to rule whether the Williams sisters and Lepchenko made themselves available for enough Fed Cup matches to be Olympic-eligible, but approval is anticipated this month.

The men's team is expected to include John Isner (10th in the ATP Tour rankings), Andy Roddick (32nd), and two first-time Olympians, Donald Young (48th) and Ryan Harrison (52nd). Mardy Fish, the silver medalist in 2004, is ranked 12th but has said he'll skip the Olympics.

In doubles, the U.S. team is expected to include third-ranked Bob and Mike Bryan and top-ranked Liezel Huber and Lisa Raymond. The men and women will each have one other doubles team, with the contestants chosen from those competing in singles.

The United States also expects to field two teams in mixed doubles, an event returning to the Olympics after an 88-year absence. Those teams will be determined after competition in the other events begins.

Venus Williams' ranking fell to 134th when she was idle for months after being diagnosed with an autoimmune disease. Setting the Olympics as her No. 1 goal for 2012, she played clay tournaments for the first time in two years and improved her ranking sufficiently, even though she lost in the second round at the French Open two weeks ago.

Williams won the gold medal in singles at the 2000 Games, and won a gold in doubles with her sister at the 2000 and 2008 Games.

"The Olympics is just the ultimate in sports," she said at the French Open. "I grew up watching those documentaries. My dad had us watch those. It was his dream for us to play there. Once I got a taste of it, it was just amazing. Every time I leave the Olympics, I go through withdrawals. It's the pinnacle of sports. I love it there."

Olympic tennis will be played at Wimbledon on July 28-Aug. 5.

Novak Djokovic remained ranked No. 1 despite losing the rain-interrupted French Open final Monday to Rafael Nadal, who won the tournament for a record seventh time. With his victory, Nadal remained No. 2 instead of dropping to third behind Roger Federer.

Maria Sharapova, who won the women's title Saturday to complete a career Grand Slam, returned to the No. 1 ranking Monday for the first time since June 2008. Runner-up Sara Errani climbed to a career-high 10th.