Rafa Nadal said he is nervous about his return to tennis after a seven-month injury layoff, and believes it may be some time before his injured knee is completely healed.

Nadal told Canal Plus television on Friday that "I'm prepared to accept that my knee may not respond well at the beginning" and has considered playing off and on during the first three months of 2013.

Syrian rebels attacked a base protecting a military industrial compound in the country's north on Friday as anti-government forces pushed forward in efforts to capture wider areas near the border with Turkey, an activist group said.

The Britain-based Syrian Observatory for Human Rights said seven rebels were killed in the attack on the air defense base in the town of al-Safira.

Oklahoma City Thunder's 12-game winning streak was ended on Thursday by the Minnesota Timberwolves, who were guided to a 99-93 victory by J.J. Barea, who scored 14 of his 18 points in the fourth quarter.

In Thursday's other games, the Miami Heat closed within a game of the Eastern Conference lead with a win over Dallas while Portland defeated Denver.

Three-time Olympian Suzy Favor Hamilton says she coped with depression and a troubled marriage by turning to a life of prostitution.

In a series of posts to her Twitter account, Favor Hamilton acknowledged working as an escort following a report Thursday on The Smoking Gun website about her double life.

Spanish football club Real Sociedad will honor its fans by bearing the names of individual club members on the shirts of its players instead of paid advertising.

Sociedad calls the fan-appreciation initiative "We carry you on our shirts."

Ferrari President Luca di Montezemolo plans to remain in charge of the Italian Formula One team even if he decides to run for a seat in the Italian Parliament.

Di Montezemolo has not yet made his plans clear but is gathering support for Prime Minister Mario Monti for another term in office.

Real Madrid will face Manchester United in a mouthwatering Champions League last-16 clash that sends Cristiano Ronaldo back to where he made his reputation, and Jose Mourinho to the club many believe he wants to coach one day.

"It is going to be thrilling for everybody," Real Madrid director Emilio Butragueno said.

The Tungurahua volcano in central Ecuador keeps spewing gas, ash and red-hot rock, forcing hundreds to evacuate from their homes.

The country's Geophysical Institute says incandescent rock shot from the crater of the 16,479-foot (5,023-meter) high mountain fell about half a mile (a kilometer) down its flanks. Explosions early Wednesday rattled windows 9 miles (14 kilometers) away, while rain-borne ash has been falling to the southwest of the crater.

A woman whose pet monkey was found wandering in an Ikea parking lot protested Wednesday with some 15 other people at a Toronto Animal Services office Wednesday in an effort to get him back.

Yasmin Nakhuda alleges the Japanese macaque, named Darwin, was illegally taken from her by animal control officials and moved to a sanctuary in Sunderland, Ontario, where he now lives.

Dirk Nowitzki has gone through his first full practice with the Dallas Mavericks since undergoing knee surgery that forced the 11-time NBA All-Star to miss every game so far this season.

Following the practice on Wednesday, Nowitzki gave no real timetable on when he might make his season debut, except to say "maybe any time after Christmas."