CAMPINAS: Cristiano Ronaldo’s World Cup may be over already after he forved t cut short training with trouble Portugal ahead of Sunday’s significant clash with the United States in Group G.

Portugal need to win after their 4-0 crushing by Germany and already know they will miss injured leftback Fabio Coentrao and suspended central defender Pepe.

Some 5,000 fans were allowed in to see the open training session today in the Moises Lucarelli stadium here which serves as Portugal’s tournament headquarters.

Ronaldo exchanged pennants with the captain of localclub Ponte Preta before the start of training.

However, after some short sprints and gentle exercises with one of the physios rather than the squad, he left the pitch with ice on his troublesome left knee and sat out the rest of the session.

Other injury absentees included goalkeeper Rui Patricio and centre-forward Hugo Almeida.

Ronaldo was injured shortly before the end of the Spanish league season and was something of a half-fit passenger for Real Madrid in their Champions League triumph over neighbours Atletico. Concern over his enduring his fitness followed him all the way to Brazil and he performed only fitfully in the defeat by Germany in Salvador.