[7] In April Princess of Sylmar was moved up in class to contest the Gazelle Stakes in which she was matched against the previously undefeated filly Close Hatches.

Her opponents included Close Hatches, Beholder (winner of the Breeders' Cup Juvenile Fillies) and Dreaming of Julia, who had won the Gulfstream Oaks by more than twenty lengths.

Ridden by the veteran Mike Smith, Princess of Sylmar was hampered shortly after the start and was not among the early leaders, but made steady progress to turn into the straight in fourth place.

"[9] On July 20, Princess of Sylmar, ridden by Castellano, started at odds of 43/20 for the Coaching Club American Oaks over nine furlongs at Saratoga Race Course.

The favorite was Unlimited Budget, also trained by Pletcher, who had finished third in the Kentucky Oaks before running sixth behind Palace Malice in the Belmont Stakes.

[13] Nonetheless, on September 28, Princess of Sylmar teamed again with Castellano for the Beldame Stakes at Belmont Park in which she was matched against older fillies and mares including Royal Delta.

On October 19, 2013, in spite of earlier denials, her connections changed their minds about running her in additional races and confirmed that she would ship west to compete in the Breeders' Cup Distaff.

[14] The race attracted a very strong field including Royal Delta, Beholder and Close Hatches: Princess of Sylmar, ridden by Castellano, was made the 13/5 second favorite.

[15] A month later, Princess of Sylmar started 1/5 favourite for the Delaware Handicap but was unable to catch the front-running Belle Gallantey and finished second, beaten two and three quarter lengths.

After a fifth-place finish in the Personal Ensign Stakes in August, 2014, Princess of Sylmar developed a case of the "thumps", an irregular spasming of the diaphragm,[16] usually caused by abnormal electrolyte imbalance,[17] and the decision was made to retire her.