“La Marseillaise” will drift out across Premier League stadiums this weekend as English football continues its show of solidarity with France over last week's devastating terror attacks in Paris.

Fans of France and England united for a moving rendition of the French national anthem prior to Tuesday's Wembley friendly and the rousing battle hymn is to be played again before each of this weekend's 10 games.

The risk of a terrorist attack is the main security fear at the Rio Olympics, a top official said Thursday, with the Paris attacks highlighting the potential for Brazil to be sucked into conflict for the first time with Islamic extremists.

"Terrorism is the number one worry," Jose Mariano Beltrame, the security chief for the state of Rio de Janeiro, told a news conference. "Brazil does not have a history of terrorism, but always works with this priority."

Novak Djokovic set up an ATP Tour Finals showdown against Rafael Nadal as the defending champion booked his semi-final berth with a 6-3, 7-5 victory over Tomas Berdych, while Roger Federer defeated Kei Nishikori to eliminate the Japanese star on Thursday.

After Federer's 7-5, 4-6, 6-4 win earlier in the day, world number one Djokovic knew he would advance to the last four if he could secure one set against Berdych in his concluding group match at London's O2 Arena.

Manchester City's French midfielder Samir Nasri will be out for a further three months due to a hamstring injury, he revealed on Thursday.

"What doesn't kill you make you stronger. I will be back better than ever see you in 3 months," Nasri wrote in an Instagram post alongside a picture of him looking pensive as he rested on a pair of crutches.

Houston guard James Harden scored 45 points, including all nine for his team in overtime as the Rockets followed the abrupt sacking of coach Kevin McHale with a 108-103 NBA victory over Portland on Wednesday.

Harden, who scored 26 points in the fourth quarter, added 11 assists for the Rockets, who snapped a four-game losing streak hours after McHale was sent packing.

Japan superstar Keisuke Honda has promised to fight for his place at AC Milan as speculation grows of an imminent move to England, local media reported Thursday.

Apparently surplus to requirements at the San Siro, Honda has been buried deep on Milan's bench after falling out with Serbian coach Sinisa Mihajlovic, but the 29-year-old on Thursday denied he had handed in a transfer request.

The prospect of Russian athletes being welcomed back into the fold for the Olympics is causing alarm amongst rivals, with questions swirling over whether the country can rebuild a credible anti-doping regime in time for Rio.

Track and field has been plunged into the worst crisis in its history over the World Anti-Doping Agency (WADA) report which uncovered a sophisticated state-supported doping program pervading all levels of Russian athletics.

Hamburg host second-placed Borussia Dortmund on Friday in the first of the weekend's Bundesliga fixtures with security under scrutiny after the Paris terror attacks and bomb scare in Hanover.

Bundesliga chiefs insist it will be business as usual in Germany's top two tiers with the weekend's blue riband game seeing Schalke host Bundesliga leaders Bayern Munich in Gelsenkirchen, which will be at 79,000 capacity.

Tight security will overshadow the resumption of Ligue 1 action in France on Friday when Nice host Lyon, one week on from the terror attacks in Paris that left 129 people dead and 350 injured.

France were playing Germany at the Stade de France on November 13 when three explosions were heard outside the national stadium. Three suicide bombers killed themselves along with one bystander.

During Brazilian star Neymar's two-and-a-half year spell at Barcelona, there has been one continuous soundbite from the softly-spoken 23-year-old: "I'm here to learn from the best".

The "best" he consistently cites is teammate and four-time World Player of the Year Lionel Messi. The two share a telepathic relationship on the field and, along with Uruguayan Luis Suarez, form one of the most lethal strike forces world football has ever seen.