Andre Fabre is not sure if Maisons-Laffitte will prove to be the ideal course for Earnshaw in Thursday's Prix Djebel.
The seven-furlong trial was used by Makfi as a prep for the 2000 Guineas in 2010, but the Godolphin-owned colt is not entered at Newmarket as yet.
He won his first start at Chantilly in September and stepped up to Group Three company at Saint-Cloud to win the Prix Thomas Bryon last October.
He was beaten less than a length by Ectot in the Group One Criterium International over a mile on his final start of 2013.
"I'm not sure if the course will suit him," said Fabre.
"He is coming back in distance but it is better to run over too short than too far at this stage.
"He would prefer it a little bit softer I think, but he won his first race on good ground."
Trainer Nicolas Clement has won the last two renewals with French Fifteen and Style Vendome but does not have a runner this year.
Jean-Claude Rouget's Kiram was a Group Two winner last year, Freddie Head's Charm Spirit was not beaten far in the Jean-Luc Lagardere while Mikel Delzangles, trainer of Makfi, is represented by Bookrunner who won his only race last year by five lengths.