The 29-year-old could face a fight to be fit for his nation's World Cup opener on Monday after leaving the session prematurely
Cristiano Ronaldo set alarm bells ringing for Portugal on Thursday as he failed to complete his side’s training session and left the pitch in Campinas with a large ice pack on his left knee.
The Real Madrid forward has been struggling with tendinosis but returned to action for 66 minutes in Portugal’s 5-1 friendly win over Ireland on Tuesday.
After that, the 29-year-old told reporters he was “99.9 per cent fit”, but participated only in stretching with his team-mates on Thursday and left the pitch with his knee in an ice pack after signing autographs for fans.
Ronaldo then watched the rest of the session from the bench and his fitness remains a cause for concern ahead of Portugal’s World Cup opener against Germany in Salvador on Monday.
The Ballon d'Or winner has been hampered by injury problems ever since Real Madrid's Champions League final win over Atletico Madrid.