THEY'VE done the rest, now they going to tackle the best. Worcestershire eventer Rosie Thomas and her 14-year-old chestnut gelding Barry's Best may have completed Burghley, Luhmuhlen and the British Open Championships at Gatcombe Park, but on May 1, they will line up for their biggest test yet.

The partnership will be competing in the Mitsubishi Motors Badminton Horse Trials across the Duke of Beaufort's beautiful Badminton park between Stroud and Bath, generally recognised as the sport's blue riband competition, virtually equal to the world championships and the Olympic Games.

"I'm really looking forward to it," said Rosie, who runs the family owned Grafton Farm Riding Centre at Bockleton, near Tenbury Wells.

"I know it will be our toughest test yet, but I'm going there with the aim of thoroughly enjoying it.

"To get a good result will almost be a bonus. Just to compete at Badminton is an experience in itself."

She has been riding almost since she could walk, coming up the usual route through the Pony Club and area competitions. Now, she is a professional instructor, chief instructor of Ludlow Pony Club and Pony Club examiner at the Grafton Farm Riding Centre.

"Horses have been my life," said the 27-year-old, "and I was really lucky to find Barry's Best." Although it might not have seemed like it at the time.

The horse was bred by Kath Blount at her stud near Cleobury Mortimer and sent to Rosie to break when he was five. The job didn't prove easy.

"He was a bit of a handful," she added, probably understating the task she faced. "But when I started to compete on him, I realised he was a nice horse after all and one with talent."

She ended up buying BB' and the pair have enjoyed a very successful time.

On their debut at Burghley in 2006 they finished 26th, jumping a superb cross country round with only 4.4 time penalties, and they also finished 18th at the four star Luhmuhlen event in Germany in 2007. They were 11th in the British Open Championships at Gatcombe in August 2007 and were 22nd at the three star Bramham.

"But I know Badminton will be different," said Rosie. "It always seems to present a special challenge and has such a great history and tradition that in itself can be rather daunting."

Certainly it will be different this year, but not in the usual way.

Last year there was controversy when several leading riders expressed their concerns about the state of the going on the cross country course and there were some high profile withdrawls. This has led to a complete reappraisal of the ground conditions and concerted action.

For the first time other users of the park, including followers of the Beaufort Hunt, have been banned from the competitive track and the course outside the deer park has been fenced off from sheep since last October. Considerable ground improvement work has been carried out and there has been sanding, seeding and fertilising. The result, according to some observers, has led to the cross country track resembling a golf course.

You can see what's coming now, because while no-one expects top riders to risk valuable horses on hard or rutted ground, the "spirit" of cross country riding is not to gallop across golf courses and in its efforts to improve, Badminton may have swung too far the other way. This saga may run on a bit yet.

As always in Olympic year, competition will be hot and among the top riders down to compete are world champion Zara Phillips and five previous winners of the Badminton trophy. There are entries from no less than 14 countries, including Brazil, Japan and Croatia, all aiming for a slice of the £278,000 prize money.

Leominster vet James Robinson has again qualified on his mother's experienced Comanche and Louise Skelton from Eardisley, Herefordshire will be going on Bit of a Barney.

BLOB The Mitsubishi Motors Badminton Horse Trials run at Badminton Park, near Stroud from Thursday May 1 to Sunday, May 4. Dressage is on the first two days, cross country on Saturday, May 3 and the final showjumping phase is on the Sunday.