Reigning Ballon d'Or Aitana Bonmati scored one goal and helped create another as World Cup holders Spain came from behind to beat Japan 2-1 in their first game of the women's Olympic football tournament on Thursday.

Spain are making their Olympic women's football debut at the Paris Games but are leading contenders to win gold after their World Cup triumph in Australia and New Zealand last year.

They fell behind against Japan in Group C in the western French city of Nantes to Aoba Fujino's early free-kick, but Bonmati soon equalised before Mariona Caldentey netted the winner in the 74th minute.

With 12 teams split into three groups of four, there is margin for error as the two best third-placed sides will advance to the quarter-finals.

That will provide some comfort for Japan, silver medallists at London 2012.

Spain's starting XI featured seven players who were in the line-up for last year's World Cup final win over England in Sydney, plus Alexia Putellas, the two-time former Ballon d'Or winner.

Japan's side included Hinata Miyazawa, the top scorer at the World Cup, but it was Fujino who opened the scoring in the 13th minute with a fine dead-ball strike which proved too powerful for goalkeeper Cata Coll.

However, Spain bossed possession and drew level midway through the first half when Bonmati rounded the goalkeeper to score.

They then grabbed the winner when Caldentey came in from the left and exchanged passes with Bonmati before firing in.

In the same group, two-time silver medallists Brazil beat Nigeria 1-0 in Bordeaux.

Former world player of the year Marta, playing in her sixth Olympics at the age of 38, had an effort disallowed for offside before setting up Gabi Nunes for the only goal late in the first half.