Caulfield Guineas day was a triumph for Robert Heathcote but he admits he faces a challenge to coax Fillydelphia back to winning form at Eagle Farm on Saturday.

Heathcote achieved his second Group One success courtesy of Solzhenitsyn in last Saturday's Toorak Handicap on a memorable day which saw Buffering add the Group Two Schillaci Stakes to his already impressive record.

The multiple Brisbane trainer's premiership winner remains mystified, however, by Fillydelphia's flop as a short-priced favourite at Eagle Farm on October 6 when she was resuming from a spell.

"Going into the race I was thinking if she won or raced well I'd pop her on a float to Melbourne but those plans went out the window pretty quickly," Heathcote said.

"It will be a challenge to get her back to the form I know she's capable of and from a punting perspective you'd have to exercise an element of caution."

While the steward's report noted Fillydelphia was lame in the off fore leg following the race, Heathcote said subsequent veterinary tests have cleared the mare of any lingering soreness.

"We've had her tested for everything and nothing has come to light," Heathcote said.

"I've had her fetlocks X-rayed. I've had her knees X-rayed. I've had a complete blood count taken and there's nothing there that would indicate any issue."

Apart from Fillydelphia, Heathcote has a strong representation at Eagle Farm with Defenceman who will be aiming for a hat-trick of wins.

"He's a bit hot between the ears but there's no doubt he has the ability to make his way through the grades," Heathcote said.

"This is a suitable race for him. Mentally he's not quite there yet but he's in winning form which is the pleasing aspect because I know the penny still hasn't dropped."

Marked has drawn barrier three in the 1800m open handicap but Heathcote believes it isn't the advantage it would appear to many observers.

"The key with him is to get him to the outside in his races and let him wind up because he just doesn't race well inside other horses," Heathcote said.

Marked has drawn single digit alleys at his past seven starts since his last win at Eagle Farm in March when he jumped from barrier 10 in an 11-horse field.