Seven-time Tour de France champion Lance Armstrong asked a US Anti-Doping Agency review board on Friday to dismiss "spurious" allegations brought against him last week.

Armstrong's attorney Robert Luskin replied to USADA's claims that the famed U.S. cyclist was part of a doping conspiracy in an 18-page letter obtained by the Washington Post and linked to Armstrong's Twitter account.

Three-time world footballer of the year Lionel Messi told The Times on Saturday that he will retire from football the day he feels he is no longer having fun.

The 24-year-old Argentinian - who scored 73 goals in 60 games for Barcelona last season, breaking the European club record of 67 goals set by Bayern Munich's Gerd Mueller in 1972-73 - hinted that for him the fun was going out of the game in general.

Germany booked their place in the last four of Euro 2012 as Joachim Loew's side hammered Greece 4-2 on Friday after dominating their quarter-final.

Germany ran riot as captain Philipp Lahm, Sami Khedira, veteran striker Miroslav Klose and Marco Reus all got on the score-sheet to cancel out Giorgos Samaras' and Dimitris Salpingidis' second-half strikes for the Greeks.

Six-time champion Boca Juniors is through to another Copa Libertadores final after holding Universidad de Chile to a 0-0 draw on Thursday, winning the semifinal 2-0 on aggregate.

The Argentine club had won the first leg 2-0 last week at home and managed the scoreless result in Chile to clinch its 10th final in Latin America's premier competition.

The Miami Heat clinched their second NBA title by routing Oklahoma City 121-106 thanks to a balanced attack and 26 points, 13 assists and 11 rebounds from superstar LeBron James.

James on Thursday was named the Most Valuable Player of the NBA Finals after leading the Heat to the crown, capturing his long-sought first championship and delivering on the promise he made to Heat fans when he came to Miami two years ago.

In the tiny locker room of a small sports club in east Jerusalem, Maher Abu Rmeileh carefully ties the black belt around his blue judo gi before beginning an intense training session ahead of the 2012 Olympics.

Participating in this year's Olympic Games, which start in London next month, is a double honor for Abu Rmeileh, who last month became the first-ever Palestinian to qualify to compete in the world tournament.

Portugal fans and neutrals hoping for a splash edition of the Cristiano Ronaldo roadshow had their appetite satisfied as he single-handedly steered his country into the Euro 2012 semi-finals by beating the Czech Republic 1-0.

Ronaldo showed the same kind of sparkle that saw the Portugal captain dominate play and claim a brace in his team's 2-1 defeat of the Netherlands last Sunday - goals he had dedicated to his son, who turned two the same day.

Germany coach Joachim Loew has insisted defending champions Spain remain the favorites to win Euro 2012 as the Germans prepare to take on Greece in Friday's quarterfinal.

Germany - who lost to Spain in the 2008 final - are the only team at these European championships to have a 100 percent record after three wins in Group B on the back of ten wins from ten in their qualifying campaign before the finals.

Canadian Grand Prix winner Lewis Hamilton said he was "super-motivated" to produce another strong performance this weekend as he aims to extend his lead in the world championship.

Thanks to his emphatic win in Montreal, the 27-year-old McLaren driver heads to the European Grand Prix with a two-point lead in what has been the sport's most extraordinary start to a season with seven different drivers winning the opening seven races.

As Maria Sharapova posed with the French Open trophy against the breathtaking backdrop of the River Seine and the Eiffel Tower, the Russian's thoughts turned from her stunning surroundings in Paris to a small patch of grass in south-west London where she hopes to cap her remarkable return to the top.

Sharapova's victory over Sara Errani in the Roland Garros final earlier this month was a cathartic moment for the 25-year-old, who had gone four years without winning a grand slam as she struggled with the aftermath of serious shoulder surgery.