World famous tennis player Roger Federer told CNN on Monday that he may make another attempt to win the Olympic singles gold medal he wants in Rio in four years' time.

The world No. 1 was beaten in the London 2012 Olympic Games by Britain's Andy Murray on Monday, the man Federer beat to secure his seventh Wimbledon title just over a month ago.

Although London 2012 officials are keen to keep secret details of Sunday's Olympic closing ceremony, former ‘’Wham!’’ singer George Michael announced his involvement on Twitter.

Michael tweeted on Tuesday: "Spending most of the next week rehearsing like crazy for the Olympic closing ceremony...

Manchester United manager Sir Alex Ferguson says Arsenal is playing hardball on the sale of star striker Robin van Persie, but he remains hopeful of luring the Dutchman to Old Trafford.

Ferguson said Arsenal is negotiating with other clubs about van Persie, with a perceived preference of selling to a non-English club, but said "we just have to persevere, hopefully it will come our way."

Calling La Liga the top league in the world, Jose Mourinho predicts a more competitive season as Real Madrid defends its title and Barcelona tries to regain the crown.

Los Blancos set Spanish records with 100 points and 121 goals last season, winning by nine points and ending the Catalans' streak of three straight titles.

Allyson Felix finally won the Olympic gold medal she craved most, gliding home with her seemingly effortless stride to take the 200-meters title and break Veronica Campbell-Brown's stranglehold on the event.

Aries Merritt added to a super sprint night for the United States, dominating the 110-meter hurdles final ahead of compatriot Jason Richardson. Behind them, Cuba's Dayron Robles, the 2008 champion, was smashing a hurdle in frustration after he pulled up lame with a right hamstring injury halfway through the race. In the heats, China's Liu Xiang, the 2004 champion, also pulled out injured.

Defending champions United States will play 2004 gold medalists Argentina and reigning European kings Spain will meet Russia in the Olympic men's basketball semifinals after triumphs on Wednesday.

The NBA "Dream Team" advanced by beating Australia 119-86 while Argentina, who upset the Americans in the 2004 Olympics semifinals but lost to them in the 2008 semis, reached the final four by beating arch-rival Brazil 82-77.

Sarah Attar became the first Saudi woman to compete in Olympic track and field, wearing a headscarf and finishing last in her 800-meter heat Wednesday.

Attar smiled broadly and waved at the crowd as her name was announced. Three minutes later, wearing a white headscarf, green long-sleeved shirt and black leggings despite the 19-degree Celsius (66-degree Fahrenheit) temperature, she drew a huge roar of approval from the crowd of about 80,000 as she strode down the home stretch.

Russia's Ilya Zakharov dashed China's hopes of a clean sweep of all eight diving gold medals at the London Olympics with a gripping victory in the men's 3m springboard final on Tuesday.

Zakharov pumped his fist in the air as soon as he resurfaced upon scoring a competition high 104.50 points on his last dive to claim the gold medal from Chinese pair Qin Kai and defending champion He Chong.

With one gold down, the Russians are trying to discount all the talk about another sweep in synchronized swimming.

But it's not working. It's clear everyone else is playing for silver.

Algeria's Taoufik Makhloufi said being disqualified from the London Olympics for not trying did not affect his focus after he came back to win the 1500m title just a day later on Tuesday.

Makhloufi was kicked out on Monday for not trying in the 800m, but reinstated when he appealed on medical grounds, citing a knee injury. On Tuesday, he beat a strong field for the 1500m gold medal.