Complex sentence: The agent purchased part interest in Haveyougoneaway on behalf of Barber after the mare won the Honorable Miss Stakes (gr. II) at Saratoga Race Course, after which she stamped her ticket to the Breeders Cup by winning Saratoga's Ballerina Stakes (gr. I).
Split into simpler sentences: The agent purchased part interest in Haveyougoneaway on behalf of Barber after the mare won the Honorable Miss Stakes (gr. II) at Saratoga Race Course. She stamped her ticket to the Breeders Cup by winning Saratoga's Ballerina Stakes (gr. I).