Rostropovich provided Aidan O’Brien with a fifth victory in the last seven renewals of the Dee Stakes at Chester.
The Frankel colt was a Group Two winner as a juvenile after claiming victory in the Futurity Stakes and having shaped with promise when fourth on his reappearance in France last month, he was the 5-2 favourite for this Listed test.
Ryan Moore was content to bide his time while his stablemate Kenya and the Mark Johnston-trained King's Proctor battled for the lead for much of the extended 10-furlong journey.
King’s Proctor lasted the longest of that pair, but was claimed on the home turn by both My Lord And Master on his outside and Rostropovich, who nipped up his inside.
It was soon clear Rostropovich had far too many guns for My Lord And Master and he swiftly kicked clear for a three-and-three-quarter-length success in this recognised trial for next month’s Investec Derby.
O’Brien said: “We were delighted with him. We thought maybe when he went beyond a mile it would suit him.
“We didn’t go beyond seven last year and we started him at a mile at Longchamp this year.
“We always hoped and thought when he stepped up it would suit him. He quickened up well. They went a nice, even pace. He relaxed lovely, so you’d have to be very happy.”
Asked about the Derby, O’Brien said: “The lads will decide if he’s one for Epsom or the French Derby. All the options are open to him.
“It never does any harm to have plenty of back-up in the big races, as last year proved – I’m not scared of running more than one, as you know.
“All these horses are bred and born to run in Classics so if we think they are up to it that’s what they’ll do.
“Because the ground in Ireland has been so bad the horses are improving massively from one run to the next.
“As we saw on Wednesday, with some of them we are even skipping their maidens just to make up for lost time.”
RaceBets and Betfair cut the winner to 20-1 from 66-1 for the big race at Epsom on June 2nd. Ladbrokes quote O’Brien’s charge at 10-1 for the French Derby 24 hours later.