FRANCIS Whittington flew the British flag on a wet and windy opening day of this year's Mitsubishi Motors Badminton Horse Trials - but overseas domination is already a major threat.

Sussex-based Whittington, a former equine dentist who is ranked 132nd in the world, led on Easy Target following a score of 36.2, which was more than 15 penalties better than their dressage performance last year.

But Highworth-based Paul Tapner, Badminton champion in 2010, clipped 0.2 penalties off that score with Kilronan, before Tapner's fellow Australian Lucinda Fredericks moved into third spot overnight aboard Flying Finish.

And New Zealand's former double Olympic individual eventing champion Mark Todd, based in Badgerstown near Marlborough, is fourth on NZB Campino, sending early warning signals to a sizeable home contingent as Britain seeks its first Badminton winner since Yorkshireman Oliver Townend triumphed five years ago.

"There was a belief we could do a dressage test in the 30s. We knew we could do it," Whittington said.

"I felt quite relaxed going in to the arena, but come Saturday (cross-country day), it is going to be a totally different ball game.

"I have been in a position when I have done good dressage scores here before, but in the past I have also ended up doing the walk of shame home on the cross-country course."

And Tapner added: "The horse was very relaxed, which is not always the case with him. I started to really enjoy myself halfway through the canter work - then I had to remind myself to keep doing my job.

"We have worked extremely hard on our four-star dressage tests, analysing every step."

With conditions forecast to deteriorate on the weekend, Saturday's cross-country challenge - designed for the first time at Badminton by Italian Giuseppe Della Chiesa - could prove decisive.

Last year's event saw 21 combinations jump clear inside the optimum time, but a single-figure total looks far more likely this time around, especially in potential stamina-sapping soft going.

A demanding logs complex 12 fences from home threatens to be particularly influentiual, and it has not escaped the attention of Britain's world number one William Fox-Pitt, who lies 28th overnight with Cool Mountain and rides his second challenger Parklane Hawk on Friday.

"There are a good few changes on the course," he said. "There are one or two jumps that have got us scratching our heads, with one (the logs) that we we hope is jumpable.

"I think it is a bit unfair because I think the horses can't sight it.

"Until that point on the course, the horse is very clear where to go, which is good cross-country designing where the rider might be a bit confused, but the horse can always see where to go.

"At the logs, the horse can't see where to go, so I think that fence could be a bit of a lottery. We will wait and see.

"There are a few jumping efforts in that last minute of the course where you have really got to have plenty of power and energy. It is not a course you can get home a tired horse, I would say."

Marlborough-based New Zealander Andrew Nicholson, the rider Fox-Pitt recently replaced at the world rankings summit and who will be a major title challenger on Quimbo and Nereo, believes Della Chiesa has built a fair test.

"The three logs on the S-bend are totally different to what we have been doing all the way up to there. You have got to slow right down, sit on your backside and have an awful lot of control," he said.

"Suddenly, you have got to come right back and do like motor racing drivers do through an S-bend. It is a very clever fence.

"I think you will see some problems there, and I think you will see some problems after that perhaps because you've had to come back and break your rhythm and are totally out of your stride pattern, then you have got to pick it all back up again.

"I think it's fair - it is what cross-country riding is about."

And Nicholson's countryman Todd added: "I think it is a proper four-star test. It is like he (Della Chiesa) has breathed a bit of new life into the course and made it a bit more interesting again.

"All the way around, we have got to be concentrating. There is plenty to jump, and he has also put in stuff to slow you down."