The Australian Bloodstock imports are among 15 nominations for the $600,000 Group 1 feature to be run at weight-for-age over the Randwick "mile".
However, Kris Lees and connections remain optimistic Mugatoo will secure one of four wildcards for the $5m All-Star Mile at Moonee Valley on March 13, and will tackle that race second-up if he makes the field.
"Whilst I have entered both Mugatoo and Collide for the Chipping Norton, at this stage both are unlikely to run," Lees said this afternoon.
"We are hopeful of knowing something early next week in regards to the All-Star Mile."
Collide was to have made his Australian debut in the Listed Parramatta Cup (1900m) – a race Lees had won the previous two years – at Rosehill Gardens last Saturday, but was a race morning withdrawal.
"He had some mucus in his throat, but is fine now," Lees said.
"I will probably wait until Saturday week and kick him off in the Listed Randwick City Stakes (2000m) at the Randwick Guineas meeting."
Collide is being aimed toward the $2m Group 1 Sydney Cup (3200m) at Randwick on April 10 during The Championships.
Whilst the pair are likely absentees from Saturday's meeting, underrated three-year-old filly Never Talk will definitely be there in search of a Group 1 victory.
Jason Collett again partners her in the $500,000 Surround Stakes (1400m) against her own age and sex.
Never Talk has won five of her eight starts and was very unlucky when she stepped up to Group 2 company in the Light Fingers Stakes (1200m) at Randwick on February 13, and was narrowly beaten by Every Rose, who led throughout.
She came from 12th at the 400m and had trouble securing clear running at vital stages in the straight.
. Lees has nominated five horses – Animate, Cristal Breeze, Frozen In Time, My Swashbuckler and Safado – for Saturday's opening $150,000 heat of the Provincial Championships on his home track.
A total of 19 horses has been nominated, and Lees will finalise his team after trackwork in the morning.
The three placegetters automatically qualify for the $500,000 Final (1400m) at Randwick on the same day as the Sydney Cup.
The Bopper (Jamie Kah) will be Lees' sole representative in the $500,000 Inglis Dash (1100m) at Flemington on Saturday.
Lees also nominated Midland, but isn't sending him south.
The Bopper will be floated to Melbourne on Wednesday, and will wear blinkers at his Melbourne debut.