Rio de Janeiro - Cristiano Ronaldo gets the opportunity to upstage fellow superstar Lionel Messi when Portugal open their Soccer World Cup campaign Monday with a mouthwatering clash against fellow European heavyweights Germany.
Having dethroned Messi as World Footballer of the Year, Ronaldo, who has been battling a left knee injury, declared himself 100 percent fit to play in the Group G match in Salvador, comfortably the stand-out fixture of the day.
"I'd like to be 110 percent, but I am at 100 percent and ready to help the national team," said the 29-year-old Real Madrid star.
"Obviously, I would like to play without pain, but in my entire career I have always had injuries and knocks to deal with, but I am ready to play."
Three-time champions Germany beat Portugal 3-1 in the third place play-off at the 2006 World Cup, 3-2 in the 2008 European Championships quarter-finals and 1-0 in the first round of Euro 2012.
Other statistics weigh against Ronaldo as Germany have won all of their World Cup opening matches since 1990.
Germany have a number of injury doubts going into the eagerly-awaited game.
But goalkeeper Manuel Neuer will return to duty after overcoming a strained shoulder and midfield star Bastian Schweinsteiger will play even though he was helicoptered to a hospital on Saturday for a knee scan.
In the group's other game on Monday, 2010 quarter-finalists Ghana face the United States in Natal having knocked out the Americans in the last 16 four years ago.
African champions Nigeria, who have taken just two points from six matches in their last two appearances at the World Cup, face three-time Asian champions Iran in Curitiba in Group F.
"Iran has faced difficulties off the pitch but we want to make our point on the pitch," said Iran's 61-year-old Portuguese coach Carlos Queiroz who cut his teeth as Alex Ferguson's right-hand man at Manchester United.
"The economic and political situation is a complete disadvantage for the team but the players are very determined."
Argentina went top of Group F at Rio's famed Maracana on Sunday when Messi scored a sparkling individual goal and created another in a 2-1 win over Bosnia.
The Barcelona superstar produced a trademark moment of magic on a night that also saw France beat Honduras 3-0, with the help of the first goal decided by goal-line technology.
Messi, hoping to secure his status as one of football's greats by shining at this World Cup, had a largely quiet game by his high standards.
But the diminutive striker provided the two decisive moments of the match for Argentina's goals.
Messi's teasing free-kick caused panic in the Bosnian defence after only two minutes and eight seconds, when the ball came off Sead Kolasinac's legs and went into his own net, the fastest own goal in World Cup history.
On 65 minutes Messi electrified the 78,800-capacity stadium with a moment of magic, jinking towards the area and unleashing a low shot which flew past Asmir Begovic in the Bosnian goal.
The only blemish for Argentina was a late goal from Bosnian substitute Vedad Ibisevic, who slid his shot below the advancing Sergio Romero.
"The second goal secured the three points and was special for me for the game I was having," said Messi, who failed to score at the 2010 World Cup.
"Everyone was anxious to do well. The result was the most important."
Elsewhere on Sunday, France made World Cup history by defeating Honduras 3-0 with the help of the first goal awarded through goal-line technology.
Karim Benzema's strike early in the second half cannoned back off the inside of an upright across the goal at Porto Alegre's Beira-Rio Stadium.
Honduras goalkeeper Noel Valladares' tried to scoop it clear but the German-manufactured GoalControl goal-line technology system signalled the ball had crossed the line, prompting Brazilian referee Sandro Ricci to whistle for a score.
There was a brief delay as Ricci consulted his fourth official while Honduras manager Luis Fernando Suarez angrily protested but Valladares's own-goal stood.
"I think it is a good solution and the goal then counts," said France coach Didier Deschamps.
The 48th-minute milestone was one of the talking points of a comfortable victory for France, whose other goals came from Real Madrid star Benzema.
France now face European rivals Switzerland in Salvador on Friday, a game which could decide who tops the group.
The Swiss snatched a dramatic last-gasp 2-1 win over Ecuador in Brasilia with Haris Seferovic netting in the fourth and final minute of injury time.