Treve gave another tip-top performance as she dispensed of old adversary Flintshire in the Grand Prix de Saint-Cloud at the Paris track.
In a repeat of last season's Prix de l'Arc de Triomphe, Criquette Head-Maarek's brilliant mare had the Andre Fabre-trained Flintshire back in second place as she recorded her fifth Group One success.
Treve was quite handy in about fourth place in the early stages, with the pace set by her stablemate Altaira until the latter ran wide into the straight.
Flintshire hit the front on the far rail, but Thierry Jarnet was wise to the move and ushered Treve (4-9 favourite) to go and win her race, which she duly did in relatively cosy fashion.
Dolniya was third without ever threatening to challenge for victory.
Treve was cut to 5-2 favourite from 11-4 with Paddy Power to win the Qatar Prix de l'Arc de Triomphe for the third year running at Longchamp on 4 October.