RACING/News: High Chaparral will be the flagship runner in an extensive Irish challenge for this week's Group One bonanza.

The Prix de l'Arc de Triomphe is the main focus of a week that contains a remarkable eight Group One races between Longchamp and Newmarket.

Aidan O'Brien yesterday conceded that a long break since High Chaparral's Irish Derby success, and a bout of the cough, has been a less than ideal preparation for the colt's likely Arc clash on Sunday with the French Derby hero Sulamnai.

However, before that, O'Brien's focus will be on Newmarket and a possible return to action for Hold That Tiger in Thursday's Middle Park Stakes.

The former 2,000 Guineas favourite hasn't run since finishing unplaced behind his stable companion Spartacus in the Phoenix Stakes in August. Both colts figure among the contenders for both the Middle Park and Sunday's Grand Criterium.

"Hold That Tiger has been back in work and it's possible he will run in one of them. We will have more of an idea about who goes where on Tuesday," O'Brien said yesterday.

Friday's Cheveley Park Stakes features the Jim Bolger pair Danaskaya and Luminata among its entries but O'Brien's juvenile filly focus is more likely to be on the Prix Marcel Bousssac.

"We have Yesterday and Miss Helga in the Boussac and they are possible runners," said O'Brien.

Yesterday finished a length and a half off Rainbows For All in the Debutante Stakes in August and that Kevin Prendergast-trained filly is also a likely Boussac runner.

However, Prendergast's main concern yesterday was the absence of recent rain at Longchamp for the Prix de l'Opera hope Rebelline.

"She is on target for the race if we get rain. We're hearing it's quite dry over there but we are still hoping for the ground to get a little more easy. Good to yielding would be ideal," Prendergast said.

"Rainbows For All is in the Boussac and I've also got Minashki in the Prix de l'Abbaye," he added.

In contrast, Dermot Weld is concerned about the Longchamp authorities possibly over-watering the track before the weekend.

"Our running plans will depend on the weather. Agnetha will run in the Abbaye if its good to firm; if it's soft Tiger Royal will run.

" Irresistible Jewel will go for the Prix de l'Opera if its good or good to firm. But we can't make out minds up until later in the week.

"It's dry at Longchamp now but I just hope they don't over-water," said Weld.

The Curragh trainer is also planning the send the double Group Three winner Dress To Thrill to Newmarket on Saturday for the Sun Chariot Stakes.

Aidan O'Brien also reported yesterday that his runners at Ascot on Saturday returned home unscathed and didn't rule out another appearance this season for the Royal Lodge third Van Nistelrooy.

"We will have to see how he is once he starts cantering again but it's possible he could have another race," he said.