Third-seeded Victoria Azarenka has advanced to the fourth round of the Australian Open, winning a matchup between champions of two warm-up tournaments when she beat Mona Barthel 6-2, 6-4 on Friday.

Azarenka, who beat four seeded players including French Open champion Li Na to win the Sydney International last week, has only lost eight games at Melbourne Park en route to the Round of 16.

Roger Federer made the most of his rare opportunities Friday against the fastest serve in tennis, cashing in with some classic returns in a 7-6 (6), 7-5, 6-3 win over Ivo Karlovic to reach the fourth round of the Australian Open.

The four-time Australian Open champion fended off Karlovic's set point in the tiebreaker with a return that brought the 6-foot-10 Croatian to the net, then lobbed just over him.

Real Madrid defender Pepe Thursday apologized for stamping on Barcelona striker Leo Messi's hand in their cup clash and said it was "unintentional", in comments published by his club.

"I was an unintentional act. All the same, if Messi was offended then I apologize to him," Pepe said in a statement published in Spanish on Real Madrid's website.

German league leaders Bayern Munich look set to welcome back star midfielder Bastian Schweinsteiger for Friday's clash against Borussia Moenchengladbach as the Bundesliga resumes after the winter break.

Germany star Schweinsteiger has been out since breaking his collarbone in the Champions League win over Napoli at the start of November, but despite sitting out training on Tuesday with a knee injury he is hopeful of playing.

Novak Djokovic and Andy Murray hit top gear on Thursday as Petra Kvitova was the only top seed to encounter difficulties at the Australian Open.

Men's favorite Djokovic, Murray and 13-time grand slam winner Serena Williams highlighted the yawning gap between tennis's best and the rest as they strolled into the third round unhindered at Melbourne Park.

Five-time champion Serena Williams brushed off fears about her injured ankle Thursday as she sailed into the Australian Open's third round with her 500th career win.

The American 12th seed, who pulled out of this month's Brisbane International after rolling her ankle on court, fell awkwardly in the final game of her 6-0, 6-4 win against Czech opponent Barbora Zahlavova Strycova.

Former world number one Maria Sharapova dismissed concerns over a series of mismatches at the Australian Open Thursday despite dropping just two games in her first two matches.

The 2008 champion blasted her way into the third round with a 6-0, 6-1 demolition of U.S. qualifier Jamie Hampton, in one of a number of crushing victories from the top women's players at this year's Open.

The director of Interpol says there is no specific intelligence the Olympics will be targeted.

Ron Noble, secretary-general of the international police agency based in France, also said Thursday that Britain does a good job of screening identification documents against the Interpol database as part of its security procedures.

Real Madrid and Barcelona resume their historic rivalry on Wednesday when the two teams meet in the first leg of the quarter finals of the Spanish Cup.

The scene is the Santiago Bernabeu before the return leg in Barcelona the following Wednesday and at stake is the first of three prizes the two giants are targeting this season.

LeBron James had 33 points and 10 assists and Chris Bosh scored 30 points as the Miami Heat rallied from a 17-point first half deficit to beat the San Antonio Spurs 120-98.

Mike Miller had 14 points off the bench for the Heat who had a dismal first half and trailed 63-49 at halftime.