Ronaldo and Robbie Williams (FIFA.com)
The former Take That frontman raised his middle finger at the end of
his performance at the Luzhniki Stadium after appearing to mouth the
words "I did this for free".
The 44-year-old performed the opening show alongside Russian soprano
Aida Garifullina, with the two singing a duet of his hit solo song
Williams had also sparked controversy in Russia two years ago for
promoting stereotypes about the country with his song 'Party Like a
He said when his performance at the ceremony was announced on Monday
that it was "a boyhood dream" and would be "an unforgettable show".
Williams was performing in front of 80 000 people at the stadium, and a global television audience of tens of millions.
The ceremony was followed by the opening match with hosts Russia routing Saudi Arabia 5-0.