Dermot Weld looks set to make a late call on the participation of his star filly Tahiyra in Saturday’s Queen Elizabeth II Stakes at Ascot.

The daughter of Siyouni has won five of her six starts to date, her only defeat coming at the hands of Mawj when beaten by half a length in the 1000 Guineas at Newmarket in May.

Tahiyra has since impressed in winning the Irish Guineas, the Coronation Stakes at Royal Ascot and the Matron Stakes at Leopardstown and Weld is keen to pitch her in against the colts on Qipco Champions Day – but admits the prospect of running on testing conditions is a worry.

“It’s pretty clear the filly herself has progressed from each of her Group Ones wins, I’m delighted with her and we want to run – but I do have to put in the caveat that she’s shown excellent speed on fast ground,” the trainer told Sky Sports Racing.

“She’s also won on soft ground and she’s a very adaptable filly, but I do have to advise that if the ground came up very heavy, she’s not a big filly and it would cause concern.

“She’s a brilliant filly and she will handle soft ground well, but I’m concerned about the weather forecast for that part of England, especially Friday night into Saturday.

“She will definitely travel over, (but) she is racing against some of the best colts in Europe and that (ground) is a concern.”

Weld has trained a host of top-class fillies during the course of his long and illustrious career and believes Tahiyra matches up to any that have gone before her.

He added: “She’s right up there. Homeless Songs was a brilliant filly the year before when she won the Irish Guineas and Tahiyra’s half-sister Tarnawa won at the Breeders’ Cup for us.

“I don’t like comparing horses from year to year. On this year Tahiyra is a very brilliant filly.”

Should Tahiyra sidestep Ascot, she would have the option of travelling to America for the Breeders’ Cup, although Weld is refusing to look beyond the weekend at this stage.

He said: “We haven’t even discussed that because it would be wrong to do so. Let’s concentrate on Saturday and let’s hope to be there.

“Champions Day has always been a very good day for me. Fascinating Rock won the Champion Stakes, we won the fillies’ and mares’ race with Sapphire and the Long Distance Cup I’ve won a couple of times with Forgotten Rules and Rite Of Passage.

“Ascot itself as a track has been very good to me. I think I’ve trained 19 Group winners at the Royal meeting and my horses always run extremely well at Ascot.

“Tahiyra is in great form, I couldn’t be happier with the filly, her final piece of work was excellent and her graph has gone the right direction throughout the year.

“I’m just very positive of a big run for Saturday.”

Tahiyra stamped her class on the Coolmore America “Justify” Matron Stakes at Leopardstown with a fourth Group One victory for Dermot Weld and Chris Hayes.

Off the track on a mid-season break since impressing in the Coronation Stakes at Royal Ascot, Weld had brought the Aga Khan-owned three-year-old along steadily for her autumn targets.

Hayes had her in the perfect spot throughout and having entered the turn for home in fourth position, she arrived on the quarters of Zarinsk still on the bridle with only Just Beautiful to catch.

She soon quickened past Paddy Twomey’s runner and Hayes was able to enjoy the final half a furlong, saluting the crowd as she crossed the line.

Tom Clover’s Rogue Millennium outran her 12-1 odds, closing into second, narrowly catching Just Beautiful, but neither were a match for the 5-6 favourite as she won by an eased-down length and a quarter.

Dermot Weld will give the Coolmore America ‘Justify’ Matron Stakes at Leopardstown “serious consideration” for his star filly Tahiyra.

The Aga Khan-owned three-year-old landed the third Group One success of her short career to date when successful in the Coronation Stakes at Royal Ascot last week.

She is currently on a short break at her owner’s Gilltown Stud with a view to an autumn campaign, with the race on Irish Champions Festival taking place on September 9.

“The Matron Stakes would certainly be a race we would definitely consider,” said Weld on the Dublin track’s website.

“Tahiyra has come out of last week well and is going on a short break at the moment and no decision has been made about her autumn campaign, but obviously the Matron Stakes will be given very serious consideration.”

Weld has won the race twice before, with Dress To Thrill (2002) and Emulous (2011), and he could also run Homeless Songs this year.

“Emulous was a very good filly I trained for Juddmonte. She was a very good winner of it. She was a very consistent filly, a multiple Group-winning filly,” he said.

“And of course Dress To Thrill was an unbeaten three-year-old filly that I trained for Moyglare. She was very talented. She won the Matron Stakes, the Sun Chariot at Newmarket and then, with a brilliant ride by Pat Smullen, won the Grade One Matriarch Stakes in California, beating the champion turf mare of America, Golden Apples.”

Above The Curve, Inspiral, Just Beautiful, Laurel, Moon De Vega and Aidan O’Brien’s Statuette, who has not run yet this season, are also among the 46 entries.