A shock for punters to start Arc Day at Longchamp with the outsider Vertical Blue ending the unbeaten record of stablemate Zarigana in the Group 1 Qatar Prix Marcel Boussac - Criterium des Pouliches (1m) for 2yo fillies.
Ridden by Alexis Pouchin for Francis Henri Graffard, the daughter of Mehmas went head to head with the Siyouni filly Zarigana over the final 200 metres to win on the bob.
Coolmore’s Frankel filly Exactly was a half-length back in third after making all the running.
Second at her first two starts, Vertical Blue broke her maiden in a conditions race at Clairefontaine on July 27 before finishing second in a Listed race at Lyon Parilly on September 11.
"It's always hard when you have two runners for different owners and they have both run brilliantly,” Graffard said.
"I felt a lot of pressure in the build-up with Zarigana. She had a tough trip and it's hard to come down the middle of the track at Longchamp with a big crowd.
"The winner had a dream run around the inside and is a filly with more experience who is progressing with every race. I'm delighted for Francis Teboul and his family."
Vertical Blue was a €50,000 purchase for Paul Nataf from the Haras Du Mont Dit Mont draft at the 2023 August Yearling Sale.
A sixth Group 1 winner for Tally-Ho Stud’s Acclamation stallion Mehmas, Vertical Blue is the first foal of the winning Sea The Stars mare Krunch, a daughter of the Listed Flame Of Tara Stakes winner Spinacre.
