Close relations to Pierro and Earthquake do battle at Randwick.
Shaken and Estriella were among a band of juveniles who accepted in both Sydney and Melbourne this Saturday and the pair being directed towards Randwick means we will see a clash of two I Am Invincible fillies closely related to two stars from around a decade ago.
Shaken is from 2014 Blue Diamond winner and Golden Slipper runner-up Earthquake, while Estriella is out of a sister to 2012 Sydney 2YO Triple Crown winner Pierro.
Estriella's dam is Madrigals, a daughter of Lonhro who is the fifth foal from Daylami mare Miss Right Note, the dam of Pierro.
In addition to Pierro, who also won a Canterbury Stakes and George Ryder Stakes at Group 1 level and placed in a Cox Plate and Doncaster Mile, Miss Right Note is also the dam of Group 2 Wakeful Stakes winner and three-time Oaks placegetter Ambience (by Street Cry).
Estriella is Madrigals third foal, the first being Polyphonic, who was the result of a trip to Japan to be covered by Deep Impact, while her now three-year-old colt by Snitzel went to Hong Kong where he races as Ever Blessing and is winless from two starts.
Estriella, a $750,000 Inglis Easter purchase who is trained by Ciaron Maher and David Eustace, will be looking to make it two wins from as many starts to begin her career after a brilliant debut win over 1100m at Gosford on June 22.
The James Cummings-trained Shaken also enters the Randwick race off a win, resuming from her debut ninth placing in early February with a dashing 1000m maiden win at Wyong on July 4.
Earthquake's three others to race are all winners, including 10-time winner Namazu (Medaglia d'Oro) and Group 2 Thousand Guineas Prelude runner-up Sumatra (Lonhro).
The blueblood pair head betting for the $150,000 ATC Thank You Trainers Handicap (1100m) with Estriella favourite from Shaken.
Estriella will be ridden by Dylan Gibbons, who is three wins astern Shaken's rider Zac Lloyd in the race for the Sydney Apprentice Jockeys' Premiership with just one meeting left in the season.
