Guus Hiddink dismissed concerns over Diego Costa's fitness by insisting the Spain striker will be available for Chelsea's crucial Champions League clash with Paris Saint Germain on Wednesday.

Costa missed Saturday's 1-1 Premier League draw against Stoke as he rested to avoid aggravating a tendon injury, but Blues interim manager Hiddink is confident his star forward will return for the last 16, second leg against PSG.

Mauricio Pochettino admits Tottenham missed an opportunity to step up their Premier League title challenge, after failing to beat 10-man Arsenal in a pulsating 2-2 draw at White Hart Lane.

Pochettino's side remain in second place, five points behind leaders Leicester, but the Tottenham manager was left frustrated after Spurs squandered a 2-1 lead against their bitter north London rivals.

Napoli moved joint top of Serie A after goals from Gonzalo Higuain, Vlad Chiriches and Jose Callejon saw them beat Chievo 3-1 on Saturday and get their title challenge back on track after a three-game mini-slump.

Maurizio Sarri's side are level on 61 points with reigning champions Juventus after a winning a hugely entertaining encounter in which Chievo, who stay 11th on 34 points, more than played their part and opened the scoring with just over a minute on the clock through Nicola Rigoni.

Novak Djokovic suffered his first Davis Cup defeat in five years on Saturday as Serbia slipped 2-1 down to Kazakhstan while Andy and Jamie Murray gave defending champions Great Britain a 2-1 lead over Japan.

World number one Djokovic and 39-year-old Nenad Zimonjic lost their doubles rubber to Kazakhstan's Andrey Golubev and Aleksandr Nedovyesov in Belgrade in the first round tie.

The International Football Association Board (IFAB), which governs the rules of the game, has approved testing of video technology to aid match officials, it was announced on Saturday.

Experiments will be carried out over a two-year period starting no later than the 2017/18 season before a final decision is taken on whether to adopt the technology permanently.

Gareth Bale is back in the Real Madrid squad for Saturday's home clash with Celta Vigo after a month and a half on the sidelines with a nagging calf problem.

"Gareth will be back in the squad. It's great news for everyone," said Madrid coach Zinedine Zidane at a press conference on Friday, although he admitted the Welshman may not feature in the game at the Santiago Bernabeu.

UEFA will introduce goal-line technology to its competitions in time for this season's Champions League and Europa League finals, European football's governing body announced on Friday.

A decision to bring in the technology (GLT) in time for Euro 2016 and for next season's Champions League had already been announced in January, but will now also be in place for the Champions League final in Milan on May 28 and the Europa League showpiece in Basel, Switzerland, on May 18.

Arsenal's hopes of capturing their first Premier League title in 12 years took a huge hit on Friday with news that goalkeeper Petr Cech faces up to a month out injured.

The Czech Republic international suffered a muscular problem at the end of Wednesday's 2-1 loss at Swansea City.

Stephen Curry tallied a game high 33 points as the Golden State Warriors defeated the Oklahoma City Thunder 121-106 on Thursday to tie the NBA record for consecutive home wins.

The Warriors' second win over the Thunder in six days was their 44th straight at Oracle Arena as they equaled the record set by the Chicago Bulls from March 1995 to April 1996.

Tokyo's long-running 2020 Olympic stadium saga has taken another twist after it emerged organizers haven't worked out where to put the Games cauldron without creating a fire risk.

After scrapping the original stadium plans altogether last year, Tokyo organizers largely neglected to factor in the Olympic flame as part of the new design, which includes wooden roof panels.