Nadal (right) will face Ruben Bemelmans on the opening day in Charleroi
Rafael Nadal says he is "100% fit" as he prepares to return from injury in Spain's Davis Cup tie against Belgium.
The world number one has not played since losing January's Australian Open quarter-final to David Ferrer, during which he injured his thigh.
Spain take on Belgium in Charleroi in the World Group first round from Friday, while defending champions Serbia host India in Novi Sad.
But Serbia will be without Australian Open champion Novak Djokovic.
The third-ranked Serb cited fatigue after winning the Australian Open and Dubai titles earlier this year, with Viktor Troicki and Janko Tipsarevic playing singles instead.
"Together with my team-mates and Davis Cup captain, I decided to rest this time," said Djokovic. "I'm confident that they will win this tie and they have my full support."
Nadal has not played for Spain since helping them win the Davis Cup for the fourth time in 2009, as he missed last year's first-round win over Switzerland and the subsequent 5-0 thrashing at the hands of France in quarter-finals.
WORLD GROUP 1st ROUND
Serbia v India
Sweden v Russia
Czech Rep v Kazakhstan
Argentina v Romania
Chile v USA
Belgium v Spain
Croatia v Germany
Austria v France
"I am fine now," said the 24-year-old. "I already start to practise a few weeks ago so I'm happy to be back in competition, back in important competition like Davis Cup.
"And, for sure, it's a motivation to be back on the team. And sure it's going to be a difficult confrontation against Belgium."
Spain will have to cope with indoor conditions in Charleroi but they have a powerful squad, with Nadal joined by world number six David Ferrer, number nine Fernando Verdasco and number 40 Feliciano Lopez.
Xavier Malisse (ranked 51), Olivier Rochus (115), Steve Darcis (129) and Ruben Bemelmans (144) make up the Belgian squad.
The remaining first-round fixtures see Sweden host Russia, the Czech Republic take on Kazakhstan, Argentina face Romania, Chile play the USA, Croatia host Germany and France travel to Austria.
The International Tennis Federation has announced a new "dead rubber policy" ahead of the weekend's fixtures to "make Davis Cup more player friendly".
Ties are the best-of-five, and the new policy states that if a tie is decided after the fourth rubber (i.e. one nation has a winning 3-1 lead after the first match on Sunday) and the fourth rubber lasts at least four sets, the fifth rubber will not be played unless both teams agree otherwise.
All five rubbers will still be played if one nation has a winning 3-0 lead after Saturday, or the tie is decided after the fourth rubber and the fourth rubber lasts only three sets. All dead rubbers will continue to be the best of three tie-break sets.
Juan Margets, ITF executive vice president and chairman of the Davis Cup committee, said: "This is part of the ITF's continued effort to make Davis Cup more player friendly, while maintaining a good spectator experience on the Sunday.
"The enhancement of the dead rubber policy came in response to requests from players, captains and National Associations."
Highlights - Nadal beaten at Australian Open