Ronaldo is set for a spell on the sidelines after just one match [AFP]

Real Madrid forward Cristiano Ronaldo will be out of action for around three weeks with a bruised right ankle sustained in the first game of the Spanish Primera Liga season.

The world's most expensive player suffered the injury as Real drew 0-0 with Mallorca on Sunday.

He will miss Portugal's Euro 2012 qualifiers at home to Cyprus and away to Norway as well as Real's league game against Osasuna and their Champions League opener against Ajax.

Meanwhile former Juventus and AC Milan coach Alberto Zaccheroni was appointed to lead Japan's national football team on Monday.

The Japan Football Association has made Zaccheroni the first Italian and the sixth foreigner to coach Japan.

The 57-year-old Zaccheroni, who won Serie A with Milan in 1999, takes over from Takeshi Okada, who stepped down after taking Japan to the round of 16 at the World Cup in South Africa.

Japan play Paraguay and Guatemala at home on September 4 and 7, with more friendlies against Argentina and South Korea scheduled in October.

Zaccheroni's first competitive tournament will be the Asian Cup in Qatar in January.

'Going to Vesuvius'

Bayern Munich on Monday announced the transfer of Argentina midfielder Jose Ernesto Sosa to Italian Serie A side Napoli.

"Sosa is going to continue his career at the foot of Vesuvius," Bayern Munich confirmed in a statement.

Sosa won Olympic gold with Argentina in 2008, a year after joining Bayern, with whom he had one year of his contract remaining.

In three seasons in the Bundesliga he has competed in 35 games, scoring three goals.

At Napoli Sosa can look forward to taking part in the Europa League where the Italian team's group rivals are Liverpool, Steaua Bucharest and Utrecht.