The 143rd running of the Kentucky Derby will happen this Saturday, at the infamous track at Churchill Downs.

The forecast is calling for a 60% chance of rain, greatly impacting how many are betting for the race. Wet track conditions can favor some horses more than others.

Of this year’s entrants, Classic Empire and Lookin at Lee have experience racing on a wet track at Churchill Downs. Classic Empire won his career debut by 1½ lengths on a sloppy track, while Lookin at Lee finished second in the Grade III Iroquois on a muddy track. Other horses in the race have never run on a wet track, so predictions are completely up in the air as to how some of the horses will handle it. Graham Motion, the trainer of Irish War Cry, said he would not change his strategy with the colt if it rains.

Trainer Chad Brown, who conditions 20-1 shot Practice Joke, said he’s as in the dark as everyone else to predict what would happen, or how the race would change in the mud.

“He doesn’t have any experience on it, but there’s nothing about the horse that tells me he wouldn’t love it. It’s an unknown. I would prefer clear racing conditions for everybody, it’s just a more enjoyable day for the people and the horses, but if it were to come up a wet track, I’m just as curious as everybody to see how my horse would handle that. Anything can happen, ” Brown said in a statement to ESPN.

When it comes to gambling for the race, no one really knows what is going to happen. Many are predicting it to be a free-for-all race.

“I think any one of seven horses can win it. No horse has ever come over from Dubai and won this race, well there’s a horse this year named Thunder Snow and it might rain on Saturday, and he won the UAE Derby on a sloppy track. He had a strong finish coming from off the pace. He’s only had two races on dirt and he’s two for two. I think he’s has an outstanding chance at 20-1 to win this race,” horse racing handicapper Hank Goldberg told CBS Sports earlier this week.

Goldberg also thinks this year’s exacta could be one of the biggest payouts in years.

“The biggest exacta I can remember is what they call the Giacomo race, Giacomo won and Closing Argument was second and it paid $9,800. You could have one of those bombs again this year.”

The distance is a 1 1/4 miles, with the track record being a mere 1:59 2/5. This is held by Secretariat from the 1973 race. NBC will have the broadcast beginning at 2:30pm EST. Post time for the big race will be a 6:34pm.