USA and China victorious

Mia Hamm and Anne Toennessen battle for the ball

USA 2-0 Norway
China 3-1 Nigeria

Defending champions the United States and China have both won their opening matches in the women's Olympic football tournament.

The Americans beat Norway 2-0 in their first Group F match, with first-half goals from Mia Hamm and Tiffany Milbrett. Only the woodwork prevented further goals.

The Norwegians, bronze medallists four years ago, had been expected to provide a stiff test but were torn apart in the first half by the attacking duo, who have amassed 366 international caps between them.

Milbrett opened the scoring after 16 minutes, slotting the ball into an empty net after her original effort had been blocked by goalkeeper Bente Nordby.

Veteran

Seven minutes later Hamm, a veteran of 209 international games, doubled the lead with a fine right-foot shot after beating the Norwegians' offside trap.

On the stroke of half-time Norway had a lucky escape when Milbrett's dipping long-range volley struck the underside of the crossbar and bounced to safety.

US coach April Heinrichs felt comfortable enough to withdraw Hamm with over 20 minutes left to conserve her for the remaining group matches.

China win

Highly rated China won their match 3-1 win against Nigeria, thanks to two second half goals from skipper Sun Wen.

Sun Wen in scintillating form

China, the 1996 Atlanta Olympics silver medallists and runners-up in last year's World Cup, looked a dominant force, with Sun particularly showing why she is regarded as arguably the finest female player in the world.

After a slow start, the Chinese were settled by an early goal from Zhao Lihong, who pounced in the 12th minute.

The 27-year-old striker collected a pass over the top before cleverly chipping the ball over Nigerian defender Yinka Kudaisi to go clear and score the opener.

In the 57th minute Jin Yan lofted a ball over a static Nigerian defence for Sun to dart in and hook a deft shot past keeper Anna Chiejine to double the lead.

Sun's second came on 83 minutes when she curled in a freekick from near the edge of the penalty area.

Nigeria scored a late consolation penalty through Perpetua Nkwocha on 85 minutes but China were rarely threatened by their African opponents.