The Manchester United star will play no part in the World Cup after damaging his collarbone in training on Friday, and will be replaced in the squad by Benfica midfielder Ruben Amorim.
Nani had struggled to hold down a regular first-team place at United following his switch to the Barclays Premier League from Sporting Lisbon in 2007.
But he emerged from the shadow of Cristiano Ronaldo following his compatriot's move to Real Madrid last summer and became an integral part of Sir Alex Ferguson's side as they narrowly lost out in the title race to Chelsea last term.
The main absentees so far – and a couple who face a nervous wait to see if they could feature – include the following marquee names:
The 34-year-old former national-team captain was all set to become the first England player to appear at four World Cups having forced himself back into Fabio Capello's plans, when disaster struck during AC Milan's 1-0 win over Chievo as Beckham broke down with a ruptured Achilles tendon.
After being set to follow in the footsteps of fellow former West Ham defender Bobby Moore, Manchester United centre-half and England captain Ferdinand did make it out to South Africa, but in the closing moments of the squad's first training session, suffered a knee injury during a challenge with Emile Heskey and will take no part in the World Cup.
Germany captain Ballack hobbled off at Wembley following a challenge by Portsmouth's Kevin-Prince Boateng during the FA Cup final, and his worst fears were confirmed when scans revealed ligament damage, denying the 33-year-old Chelsea midfielder the opportunity of a third World Cup appearance.
Essien had not played for Chelsea since December because of a knee problem, and so looked doubtful to be involved in the Black Stars' World Cup campaign.
Essien's absence is a major blow to the Africans' hopes of progressing from a group which also includes Germany, Australia and Serbia.
(Portugal, collar bone)
The forward, who began to come to the fore for Manchester United during the domestic season, damaged his collar bone in training and was ruled out of the tournament. Nani sparkled in his first season at Old Trafford without compatriot Ronaldo and was expected to line-up alongside the Real Madrid forward in South Africa. His absence will weaken Portugal's attacking options.
JOHN OBI MIKEL
The third of Chelsea's World Cup crocks also suffered a knee problem and underwent minor surgery in May. Although he joined up with the squad in South Africa, the 23-year-old decided he would not be fit enough to take part and pulled out of the tournament.
(Ivory Coast, broken arm)
Ivory Coast manager Sven-Goran Eriksson will be praying Drogba can fend off Chelsea's injury jinx after suffering a broken bone in his arm during a friendly against Japan – leaving the striker in a race against time to be fit to play in South Africa, when Ivory Coast will face Brazil, Portugal and North Korea in the 'Group of Death'.
Winger Robben, the star of Bayern Munich's run to the Champions League final, has vowed to do everything possible to play at the World Cup, despite suffering a torn hamstring in Saturday's 6-1 friendly win over Hungary. The player himself admits the injury would normally take up to six weeks to heal, so his participation still looks in doubt.