HANGZHOU, China - Star striker Ragnhild Gulbrandsen plundered a hat-trick as former champions Norway stormed into the women's World Cup quarter-finals with a 7-2 demolition of already eliminated Ghana Thursday.

Norway's Solveig Gulbrandsen (in red) and Ghana's Florence Okoe fight for the ball during their Group C soccer match of the 2007 FIFA Women's World Cup in Hangzhou September 20, 2007. [Reuters]

Gulbrandsen pounced in the 39th minute and added another two after half-time to become the tournament's top scorer with five goals in three games, and book the European heavyweights' place in the last eight.

"I'm really surprised. If someone had said that to me before the World Cup (that she would head the scoring) I wouldn't have believed them," the 30-year-old Gulbrandsen said.

Norway, World Cup champions in 1995, finish top of Group C and now take on hosts China in the last eight in Wuhan on Sunday.

Coach Bjarne Berntsen credited their win to intensive preparation against Ghana, and making the most of their chances at goal.

"I think this game we were very effective," said Berntsen, but added that there was room for improvement.

"It's very important that we improve, though, because I don't think we played our best football today, we were certainly too casual in defence."

Norway began the bombardment in the fourth minute, Lene Storlokken chesting down and rifling home after being picked out with a header.

Norway, who needed only to draw to qualify, immediately eased off the pace and appeared to be coasting at the near-empty Dragon Stadium.

But after shouts of encouragement from goalkeeper Bente Nordby, one of the best goalkeepers in the game, Gulbrandsen doubled their advantage with a close-range volley from Siri Nordby's cross.

Captain Ane Stangeland Horpestad kept the scoreboard ticking over with a sweetly struck penalty on half-time, and after the break 16-year-old substitute Isabell Herlovsen beat two defenders and slotted home past keeper Gladys Enti.

Enti was caught out of position for Norway's fifth with Leni Larsen Kaurin gathering the rebound from her misfired shot and passing for Gulbrandsen's second.

Gulbrandsen struck again three minutes later, latching onto a free kick and volleying past a diving Enti. Substitute Lise Klaveness rubbed salt into the wound, firing home on 69 minutes.

Ghana left with some consolation as captain Adjoa Bayor thumped home a free-kick on 73 minutes and Florence Okoe coolly converted a penalty with 10 minutes left.

"We have players who are very young and playing for the first time at a World Cup, so it is all an experience for them," said Ghana coach Isaac Paha.

Norway finished second in the inaugural 1991 World Cup, won the 1995 edition, came fourth in 1999 and were losing quarter-finalists four years later.