DOUGIE Costello's decision to turn his back on jumps racing and concentrate full time on the Flat is really starting to pay dividends as he enjoyed his first Group 2 success thanks to Quiet Reflection in the Sandy Lane Stakes at Haydock last Saturday.

The impressive win saw the filly jump to the head of some markets for Royal Ascot, with the Haydock victory following a win in the Group 3 Prix Sigy at Chantilly, and Costello could hardly contain his excitement about Quiet Reflection's future prospects.

"That's massive for me and the team," he said. "She's just a push-button filly. In France, she was a little bit keen to post and probably didn't travel as well as she did today. I felt she could be a 10lb better filly.

"Today she travelled, I was happy with where I was and she's won going away. She's settling this year compared to last year and, wherever she is in a race, they'd have to have a lot of speed to catch her. She has instant speed."

The horse is trained in Middleham by Karl Burke, who was also in a bullish mood following Quiet Reflection's victory and is leaning towards a tilt at the Group 1 Commonwealth Cup at Royal Ascot.

Burke did suggest he could be tempted by the Group 1 King's Stand Stakes over five furlongs should the ground come up soft, but said of the six-furlong Commonwealth Cup: "There's an American horse (Acapulco) that will probably give us a nice lead and hopefully we can cut it down in the last furlong."

Reflecting on the style of her victory on Saturday, Burke added: "There was all this talk of her not getting six, but I was always confident she would.

"She's a different filly to the one who went to France, she's matured and our horses weren't particularly running well at that time.

"The idea probably wasn't to sit that far back, but we were never too far away. When Dougie came cruising up on the outside, I thought he was going to hit the front a bit too soon, but she's shown that fantastic turn of foot."

The new week started with more success for Middleham trainers as Mark Johnston sent out Revolutionist to win the Racing UK Zetland Gold Cup at Redcar.

The giant four-year-old was a winner at Newmarket a week and a half ago, but a 4lb rise was not enough to stop the 8-1 scorer.

Well-ridden by the excellent Joe Fanning, Revolutionist sat in second early on before Eternal dropped away and he fended off all-comers in the straight.

Central Square, the 9-4 favourite, finished second, but he was a length and a quarter away at the line.

Deirdre Johnston, wife of the winning trainer, said: "He's absolutely enormous, but he's so genuine.

"He's won a few over a mile, but it looks like stepping him up in trip has brought about some improvement.

"If he emulates last year's winner (Fire Fighting), we'll be delighted."

Today, the fillies take centre stage in the Investec Oaks, headed by impressive 1,000 Guineas winner Minding, one of nine declarations.

Minding, who suffered a shock defeat to Jet Setting in the Irish 1,000 Guineas less than a fortnight ago, will be joined by stablemates Seventh Heaven and Somehow at Epsom.

The Aidan O'Brien-trained three-year-old will be bidding to become the first filly since Kazzia in 2002 to complete the 1,000 Guineas and Oaks double.

Minding has been installed as the 10-11 favourite to bounce back from her shock defeat at the Curragh last month and provide her trainer with a sixth win in the Oaks.

She could become the first filly to be sent off as an odds-on favourite in the Oaks since Reams Of Verse triumphed at 5-6 in 1997, while today's Group 1 will be the first single-figure field since Ouija Board beat six rivals to score in 2004.

Tomorrow's Derby looks much more open, with a big field guaranteed. Once again, O'Brien looks an obvious starting point.

However, the master of Ballydoyle looks like he could saddle five in the world-famous Classic, with Ryan Moore on US Army Ranger.