World No. 1s Roger Federer and Victoria Azarenka will be among those on hand playing for gold at the London Olympic Games, which will stage the tennis portion of the event from July 28-Aug. 5.

The tennis tournament will boast its strongest-ever Olympic singles entry and be held at the site of the famed Wimbledon Championships -- the prestigious All England Lawn Tennis Club.

The Swiss Federer is fresh of his seventh Wimbledon title and 17th Grand Slam championship, while the Belarusian Azarenka has held the No. 1 ranking for a majority of 2012 following her first-ever major title at the Australian Open back in January.

Federer still needs Olympic gold to complete the coveted career Golden Slam, which is all four majors and Olympic gold.

The reigning Olympic gold medallists in singles are Spain's Rafael Nadal and Russian Elena Dementieva, who has since retired from professional tennis. The reigning French Open champion Nadal, unlike his great rival Federer, does own a career Golden Slam. He beat Chilean Fernando Gonzalez in the 2008 gold-medal match in Beijing, while Dementieva topped fellow Russian Dinara Safina in the women's gold-medal bout in China. Gonzalez, Dementieva, who was also a silver medalist in Sydney in 2000, and Safina will not be on hand in London, as all three are now retired from the game.

The United States will send 6-foot-9 John Isner, former world No. 1 Andy Roddick, Ryan Harrison and Donald Young to play men's singles, while the U.S. women's singles contingent in London will be Wimbledon champ Serena Williams, 2000 gold medalist Venus Williams, Christina McHale and Varvara Lepchenko.

Several other stars will vie for singles gold in London, including Beijing bronze medalist, reigning Aussie Open and U.S. Open champ and former No. 1 Novak Djokovic of Serbia; British hopeful and 2012 Wimbledon runner-up Andy Murray; French slugger and former Australian Open runner-up Jo-Wilfried Tsonga; gritty Spaniard David Ferrer; big Czech and former Wimbledon runner-up Tomas Berdych; towering Argentine and former U.S. Open champ Juan Martin del Potro; and rising massive-serving Canadian Milos Raonic.

Azarenka and Serena Williams can expect to be challenged by a bevy of women, including Poland's Wimbledon runner-up Agnieszka Radwanska; former No. 1 and reigning French Open champ Maria Sharapova of Russia; reigning U.S. Open titlist Sam Stosur of Australia; former Wimbledon champ Petra Kvitova of the Czech Republic; German left-hander Angelique Kerber; former top-ranked Dane Caroline Wozniacki; and outgoing Belgian star Kim Clijsters, who will retire from tennis for a second time following this summer's U.S. Open, where she is a three-time winner.

Sharapova needs an Olympic gold medal to complete a Golden Slam. She became a career Grand Slam winner by virtue of her first-ever French Open title last month.

The only top-20 players expected to miss the Games are 2004 silver medalist Mardy Fish of the U.S. and France's Marion Bartoli, who was a Wimbledon runner-up back in 2007.

Each singles draw will be comprised of 64 players.

The Americans will boast doubles teams such as the mighty twin Bryan brothers, Bob and Mike, as well as a hard-hitting tandem of Isner and Roddick, while U.S. women will be well represented with the Wimbledon champion and reigning Olympic gold medalist Williams sisters as well as Liezel Huber and Lisa Raymond. Serena and Venus captured gold in Beijing four years ago and also secured the Olympics' top tennis prize in Sydney in 2000. The Bryans captured Olympic bronze four years ago.

The reigning men's doubles gold medallists are Federer and fellow Swiss Stan Wawrinka, who will be in London to defend their crown.

Thirty-two teams will make up each of the doubles draws.

Mixed doubles will be included in the Games for the first time since 1924, when an American duo of Hazel Wightman and Norris Williams came out on top. Entries for the 16-team event will be determined on site from those players already participating in singles or doubles.

Tennis was a part of the first modern Olympic Games in 1896, and the first woman to win an Olympic medal in any sport was British tennis player Charlotte Cooper in Paris in 1900. After the 1924 Paris Games, tennis withdrew from the Olympics but returned as a demonstration event in Los Angeles in 1984 and as a full-medal sport in Seoul in 1988.

The All England Club previously staged Olympic tennis in 1908 at its old site on Worple Road. This is the first event to be held on grass since tennis' return as a full-medal competition.

Forty-five countries will be represented at the All England Club.