After 23 wins since the start of 2006 Mexican Lorena Ochoa is clear at the top of the women's golf world rankings.

But the 27-year-old goes into the Ricoh British Open at Royal Lytham tomorrow without a victory in her last six starts and very determined to reassert her authority.

"I haven't had great results in the last few tournaments, but that was down to one bad round rather than bad golf," said Ochoa, runaway winner of the title at St Andrews two years ago.

"I'm hitting my driver better and I think that will be important for this week.

"The course is softer than it was when we played here in 2006. Then you could land the ball 10 or 15 yards short of the green and bounce it up there.

"Not today. The grass is very green, the ground is not very hard and the rough is longer than before."

It was 2001 when Ochoa last had a season that did not include at least one top-10 finish in the majors - and that was hardly surprising considering she was 19 and played only one of them.

This year she has so far come 12th, 23rd and 26th in them and last week she was down in 40th spot at the Evian Masters in France.

In the opening two rounds Ochoa is paired with Sunday's winner Ai Miyazato and England's Karen Stupples, winner of the title at Sunningdale in 2004.

The tournament boasts 29 of the world's top 30 players and is the last qualifying event for both the European and United States Solheim Cup teams.

Defending champion is South Korea's Jiyai Shin, who triumphed by six at Sunningdale last year and has since gone on to record a further four LPGA Tour titles and jump up to fourth on the world rankings.

The 21-year-old, whose mother was killed in a car crash five years ago, already has 28 professional victories to her name - and has also recorded a pop song in her home country.