The key questions as Rostropovich bids to play familiar tune for Aidan O'Brien

Homeserve Dee Stakes | Listed | 1m2f 70y | 3yo | ITV4/RUK

Where would the race be without Aidan O'Brien?

Chester must be indebted to Aidan O'Brien for keeping the credibility of the Dee Stakes as an Investec Derby trial afloat.

Without him the Listed race's reputation would be sunk in the river after which the contest is named.

The last horse to win the Dee and go on to triumph at Epsom was Kris Kin in 2003, ending an era when the race had also been a stepping stone to the Derby for Oath and was won by Pentire, who went on to Group 1 success in the King George and Irish Champion Stakes.

Yet O'Brien keeps coming back, claiming victory in four of the last six years including with Cliffs Of Moher and Astrology, who finished second and third in their Derbys, and Magician, a subsequent Breeders' Cup Turf winner. In the two years he missed out neither winner ran at Epsom.

So there should be clues to be found from the performances of Rostropovich and Kenya, who are two of only three runners entered in the Derby.

Rostropovich, a son of Frankel who cost 1.1 millions gns as a yearling, was a Group 2 winner last year in the Futurity Stakes and finished third in the Group 1 National Stakes. He finished fourth of five in a Group 3 race at Longchamp last month on his return.

Kenya finished third of four behind stablemate Gustav Klimt at Leopardstown last month but was a Group 3 winner last year.

O'Brien said: "Both of them will be stepping up in trip and we've been happy with them since their first runs of the season, at Leopardstown and Longchamp respectively.

"They'll be racing on better ground this time and that should suit."

Can Godolphin nullify O'Brien challenge with gelding Rastrelli?

Rastrelli captured the Newbury race in which Enable finished third before embarking on a winning spree that took in this Chester meeting before wins in the Oaks, King George and Arc last year.

He won't be winning a Classic or an Arc but he could have a long racing career ahead of him with Godolphin if he can underscore the potential he showed at Newbury, where he ran out a two-and-a-quarter-length winner, conceding 3lb to his rivals.

Trainer Charlie Appleby said: "Rastrelli is stepping up in class but has some decent form lines behind him. He saw the trip out well when winning at Newbury the other day and goes there as a player."

Can My Lord And Master step up from Epsom experience?

My Lord And Master has already had a spin round Epsom, where he finished strongly to go down by a head to Crossed Baton in the Investec Blue Riband Trial.

He is the only other horse in the field entered in the Classic and probably needs to win to justify a return visit, but that is not out of the question.

Trainer William Haggas said: "I would prefer to run at a mile and a half but I ran Young Rascal in the Vase. He needs a bit of dig in the ground to be seen at his best. I think they are going to get a bit of rain and as long as it's not fast he should be fine.

"He should run to his best. He has a chance. He's not a bad horse."

What they say

Tom Dascombe, trainer of Finniston Farm
He was working the house down before he made a winning debut at Haydock last year and we then ran him in the Superlative Stakes at Newmarket, where he was beaten only a couple of lengths by Gustav Klimt. He returned in the Free Handicap last month and showed his inexperience as he was very green, but he did all his best work at the end, which was particularly encouraging. I thought he was a miler but he already looks like he needs further.

Charlie Johnston, assistant to Mark Johnston, trainer of King's Proctor
It's a big jump up in class for King's Proctor but we've always thought a lot of him. We're hoping the better ground will see him in a better light – on the bare figures he's got a lot to find but we hope he'll show he's up to this class.

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