JESSICA Harrington and Frankie Dettori formed an unlikely alliance to win the Group 1 Coronation Stakes at Royal Ascot with Alpine Star.

Harrington went into the winter with an embarrassment of riches in the three-year-old filly department, seemingly having three top-class inmates.

However, Milisle was beaten in the 1000 Guineas at Newmarket and Albigna fared little better when favourite for the Irish version.

The latest challenge for early-season Group 1 honours came with Alpine Star (9/2), who was making her seasonal debut and relished the step up to a mile, powering clear in the closing stages.

A half-sister to Alpha Centauri, who won this race herself, Alpine Star was one of the first off the bridle as Run Wild set a strong pace.

When she capitulated, though, Guineas runner-up Cloak Of Spirits took over only to be challenged by Quadrilateral, while Alpine Star shot through a gap on the rail when her stamina kicked in.

American raider Sharing made ground from the rear into second, but Alpine Star was going away by the line, winning comprehensively by four and a half lengths.

Dettori said: “It’s great. I really fancied the filly, but I didn’t want to jinx it. I kept quiet. Jessie approached me about 10 days ago when she knew their jockey couldn’t fly here.

“I knew she was an exciting ride. I asked John (Gosden) permission to ride this filly and he said yes. Everything went to plan. I had a decent draw. I hit a flat spot, but I got a split on the fence and the rest is history.

“I’m delighted for the Niarchos family. Maria (Niarchos) has supported me in the past. I think it was my first ride for Jessica.

“Shane Foley rang me this morning. It has been a team effort.”

Dettori has now won every Group 1 that is run at Royal Ascot.

He added: “Now I can say I have really conquered Ascot completely now. It’s a big tick in one of my boxes. I’m delighted for all people concerned.”

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