A decision on whether Jack Hobbs takes his place in the Epsom Derby will be made after trainer John Gosden walks the track on race morning.

Gosden is concerned the the ground will be too firm if the forecast showers do not arrive by Saturday morning.

Stablemate and pre-race favourite Golden Horn is comfortable on harder ground but Gosden would ideally like a little ease in the ground for Jack Hobbs who will run for the first time in Godolphin's blue silks.

"The race is at 4.30pm, and if it is sunny and breezy I would be concerned," Gosden said on the Godolphin website.

"I will walk the track beforehand.

"Godolphin and the other partners are aware that I will be doing that.

Andrew Balding is in a similar position with Elm Park, who missed the 2000 Guineas at Newmarket earlier in the season because the ground was too fast.

"It sounds like they (thunderstorms) are going to be localised so let's hope we're lucky and that some of them hit Epsom," he said.

"He'll run, but I'd obviously be a little bit more apprehensive running him (on fast ground).

"I'm sure it will be safe ground. There's not a lot I can do.

"I'm sure whatever happens he'll run a decent race."

The official going at Epsom on Thursday evening was good.

The Dermot Weld-trained Zawraq is the significant omission from the Derby after failing to recover from a leg problem detected earlier in the week.

Aidan O'Brien has declared Giovanni Canaletto (Ryan Moore), Hans Holbein (Seamie Heffernan) and Kilimanjaro (Joseph O'Brien).

Derby betting:

William Hill bet: 6-4 Golden Horn, 9-2 Jack Hobbs, 6-1 Giovanni Canaletto, 13-2 Elm Park, 12-1 Hans Holbein, 14-1 Success Days, 20-1 Epicuris, Kilimanjaro, Storm The Stars, 40-1 Moheet, 66-1 Rogue Runner, 250-1 Carbon Dating.