Ronaldo in Olympic squad
Ronaldo has been named in the 18-man squad to play at the Athens Games next month.
If Ronaldo does make the trip to Greece he will miss the start of the new Premiership season.
The news will come as a major blow to Sir Alex Ferguson as he will be keen to have his strongest squad available for the beginning of the new campaign.
Fulham manager Chris Coleman could also be affected as Luis Boa Morte has been included in the squad as one of their three overage players along with Stuttgart defender Fernando Meira and Boavista's Nuno Frechaut.
New Chelsea signing Tiago is also included in the squad meaning he will miss the beginning of the new season.
Newcastle midfielder Hugo Viana, who has returned to former club Sporting, is also included in the squad along with ex-Tottenham man Helder Postiga.
Portugal who are drawn with Iraq, Morocco and Costa Rica in Group D fly out to Greece on August 8 before starting their campaign three days later.
Full squad:
Moreira (Benfica), Bruno Vale (Porto); Frechaut (Boavista), Ricardo Costa (Porto), Mario Sergio (Sporting Lisbon), Fernando Meira (Stuttgart), Bruno Alves (Porto); Carlos Martins (Sporting Lisbon), Danny (Sporting Lisbon); Raul Meireles (Porto), Bosingwa (Porto), Luis Boa Morte (Fulham), Hugo Viana (Sporting Lisbon), Tiago (Chelsea), Cristiano Ronaldo (Manchester United); Jorge Ribeiro (Gil Vicente), Lourenco (Belenenses), Helder Postiga (Porto)
