Betting favorites were upset in all three preps for sophomore classic races held on very heavy ground at Longchamp Sunday.In the first of the three, Denon outdueled Tarzan Cry in the stretch, upsetting favored Okawango in the Prix de Fontainebleau (Fr-III), a prep for the Poule d'Essai des Poulains-French Two Thousand Guineas (Fr-I). The winner and the favorite were both making their seasonal debuts in the one-mile race.Denon (Pleasant Colony--Aviance, by Northfields) was bred in Kentucky by Flaxman Holdings Ltd. and races in the colors of the Niarchos Family. The Jonathan Pease trainee won by 1 1/2 lengths over Tarzan Cry, with Okawango third in the six-horse field. As a juvenile, Denon won one of two starts, finishing a half-length second in the Prix Thomas Bryon (Fr-III) in his lone defeat.In the 1 5/16-mile Prix Greffulhe (Fr-II), Maille Pistol led all the way in defeating heavy favorite Sagacity. A half-brother of Arc de Triomphe (Fr-I) winner Sagamix, Sagacity disappointed in finishing fourth in the Prix du Jockey Club-French Derby (Fr-I) prep.Maille Pistol (Pistolet Bleu--Bric Mamaille, by Bricassar) remained unbeaten as a 3-year-old with the win, his third in four career starts. Bred in France by M. Bertrand Compignie, Maille Pistol is trained by Jean-Claude Rouget for owner Michel Roussel.In the last of the three preps, Quarter Note led from the start under Yutaka Take and held on to win the Prix de la Grotte (Fr-III), a prep for the Poule d'Essai des Pouliches-French One Thousand Guineas(Fr-I). Favored Amonita finished two lengths back in second.The win improved Quarter Note's career record to three wins from eight starts. A 3-year-old filly trained by Henri Alex Pantall, Quarter Note (Danehill--Qirmazi, by Riverman) was bred in Kentucky by Darley Stud.