City of Troy will face 12 top-class rivals when he challenges for further top-level glory in the Group 1 Juddmonte International Stakes at York on Wednesday, while the Breeders’ Cup Challenge Series field vie for a free place in the $7 million Breeders’ Cup Classic.

In addition to the 1 1/4-mile Juddmonte International Stakes for three-year-olds and older, the opening Ebor Festival program also includes the Acomb Stakes (G3) for two-year-olds, which is an automatic qualifier for the $1 million Breeders’ Cup Juvenile Turf Stakes (G1).

Two more Breeders’ Cup Challenge Series races take place in York this week. Thursday’s Yorkshire Oaks (G1) offers a place in the $2 million Breeders’ Cup Filly & Mare Turf, and Friday’s Nunthorpe Stakes (G1) provides an automatic place in the Breeders’ Cup Turf Sprint.

The city of Troy faces its toughest test yet

City of Troy has silenced the doubters since his flop in the 2000 Guineas Stakes (G1) in May with a spectacular Derby (G1) success and a solid win in the Coral-Eclipse Stakes (G1) at Sandown last month. The son of Justify has never faced such a strong field and there is no doubt that it would be the best performance of his career if he could add a fourth Group 1 title to his resume on Wednesday.

Aidan O’Brien, who also manages likely frontrunner Hans Andersen, is just one win away from becoming the most successful trainer in the history of the famous competition. He has won the Juddmonte International six times and a victory on Wednesday would take him past Sir Michael Stoute.

“We have been pleased with City of Troy since the Eclipse,” said O’Brien. “He is a horse that has always captured everyone’s imagination and he is in very good form at the moment. He didn’t have a good time at Sandown to show his strengths but we were pleased with his performance and were pleased for him in the Derby before that and have been looking forward to York for a long time.”

Calandagan outscored his rivals by six lengths in the King Edward VII Stakes (G2) at Royal Ascot. The three-year-old Gleneagles gelding will be competing at the highest level for the first time as he looks for a fourth consecutive win. His trainer Francis-Henri Graffard has already tasted Group 1 success here last month, thanks to Goliath in the King George VI & Queen Elizabeth Stakes (G1). The Jerome Reynier-trained Zarakem also travels across the Channel from France.

Juddmonte has decided to run his star mare Bluestocking against the colts rather than wait until Thursday’s Yorkshire Oaks (G1). The Ralph Beckett-trained 4-year-old won the Middleton Fillies’ Stakes (G2) over this course and distance on her seasonal comeback and was most recently second to Goliath in the King George at Ascot. She is the only mare in the line-up.

Ambience Friendly goes into this race having finished second to City of Troy in the Derby at Epsom and third in the Irish Derby (G1). Meanwhile, Jeff Smith’s Ghostwriter will renew his rivalry with City of Troy after being beaten just two lengths behind O’Brien’s charge in the Eclipse at Sandown.

Alflaila holds an incredible record of four wins in five starts at York, including defeating a strong field over this distance last time out in the York Stakes (G2).

Two horses moving up the distance from a mile are Docklands, who last finished second to Charyn in the Queen Anne Stakes (G1), and the William Haggas-trained Maljoom, who finished second to Notable Speech (GB) in the Sussex Stakes (G1) at Goodwood last month.

Kikuka Sho (G1) winner Durezza will make his British debut and Israr and Royal Rhyme complete the lineup.

Godolphin’s purchase of Ruling Court for around $2.5 million makes him the top name in the Acomb Stakes. The son of Justify started at odds of 4-9 at Sandown last month and despite showing signs of immaturity in the early stages of the race, he eventually pulled away from his rivals in style to win by 5 1/2 lengths.

His trainer Charlie Appleby, who has never won the Acomb Stakes, said: “I was very pleased with his performance on his debut and it’s always a bit different when you have an expensive Breeze horse compared to an expensive sale horse. The plan was always to go to Sandown, we always hoped he would do what he did and then go on to the Acomb.”

Aidan O’Brien will have a strong presence at York this week. He has elected to run The Lion in Winter, a maiden winner on his debut at The Curragh. Ryan Moore will ride the son of Sea The Stars.