Ronaldo took his tournament tally to four goals when he charged into the box, timing his run to perfection in the fourth minute to power in his header.
Victory sent Portugal top of Group B on four points ahead of Spain's game against Iran in Kazan, as a second straight defeat for Morocco condemned the African nation to an early exit in their first World Cup appearance since 1998.
It all started with Ronaldo's celebration after netting a hat trick against Spain to single-handedly carry Portugal to a 3-3 draw with the world powerhouse.
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Newcastle boss Rafa Benitez is a firm admirer of the player, and would be interested in a loan move for the 22-year-old this summer.
There's an old joke that Portugal (and Greece) can't play great soccer because every time they get a corner, they open a cafe.
Instead, it was the less flamboyant players who stood out, such as goalkeeper Rui Patricio, defenders Pepe and Jose Fonte, and the calm and composed William Carvalho in front of the defense.
Ronaldo, was seen rubbing his chin whenever he scored which many took it as a subtle dig towards rival Lionel Messi. Against Morocco, his thumping header handed the Seleccao an important win which has all but ensured their progress in the next round. With Morocco already out, Spain, Portugal and Iran are fighting it out for the two qualification berths.
The Seleção have ridden their luck and relied on captain Cristiano Ronaldo's heroics having been second best in both matches played thus far.
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Mark RALSTON / AFP Iceland's defender Kari Arnason (C) falls past Nigeria's midfielder John Obi Mikel . With his double, Musa is now the highest-scoring Nigerian at the World Cup finals with four goals.
In all of the knockout matches, Portugal had less possession than their opponents, ranging from 41 percent against Croatia to 47 percent against France, and the same has happened in their opening two games at the World Cup.
Away from the football, Burger King has apologized for an online ad offering burgers to Russian women who get impregnated by football players during the World Cup.
"Even if you want to draw up plans for Ronaldo, he always finds a way out", Renard had said on the eve of the contest. I doubt if that guy will see another minute of action in the World Cup.
The win means Russian Federation and Uruguay both have six points in Group A, with Egypt and Saudi Arabia eliminated with zero points apiece.
Ahmad Shahzad tested positive for doping
What are the ICC rules? Sources informed that Shehzad's test was taken during a recent domestic cricket tournament. As per the rules, the opening batsman is set to be suspended from global cricket for a period of three months.
He said: "I'm very happy".