Dubai Sky and Firing Line were the big movers in early Kentucky Derby wagering after picking up wins in Road to the Derby races over the weekend.

On Saturday, Dubai Sky pulled off the mild upset in the $550,000 Spiral Stakes (G3), his first start on polytrack after racing on turf in his first four starts.

Trained by Hall of Famer Bill Mott, the colt overcame an outside draw and racing wide much of the trip to rally for the win, returning $16.80 for a $2 win wager.

The colt picked up 50 Derby points, enough to get into the starting gate in Louisville. The colt was not previously nominated to the Triple Crown, but his connections ponied up the $6,000 late nomination fee after his Spiral win.

The colt was not even listed last week at [custom:bovada-link], and opened this week at 15/1, good for fourth choice among the Kentucky Derby horses.

Firing Line demolished his competition on Sunday to win the $800,000 Sunland Derby (G3), rolling to a 14 ¼ length victory as the betting favorite, paying just $2.40 for the win.

In his two previous starts, the colt had come up short to Dortmund, both in the Los Alamitos Futurity (G1) and Robert B. Lewis (G3), beaten ahead in each outing.

After his Sunland Derby victory, his early Derby betting odds at [custom:bovada-link] dropped from 25/1 to 15/1.

American Pharoah remains the favorite, his price dropping this week to 4/1. The Bob Baffert trainee makes his final prep in the $1 million Arkansas Derby (G1) on April 11.

His stablemate Dortmund remains the second choice, his price dropping from 7/1 last week to 6/1. His final prep for the Run for the Roses comes in the $1 million Santa Anita Derby (G1) on April 4.

Odds to Win 2015 Kentucky Derby at Churchill Downs at [custom:bovada-link] as of March 24:

American Pharoah 4/1 Dortmund 6/1 Carpe Diem 10/1 Firing Line 15/1 Dubai Sky 16/1 Far From Over 20/1 El Kabeir 20/1 Competitive Edge 20/1 Khozan 20/1 Upstart 20/1 International Star 20/1 Itsaknockout 20/1 Prospect Park 20/1 Ocho Ocho Ocho 25/1 Daredevil 25/1 Ocean Knight 25/1 Far Right 30/1 I Spent It 33/1 Lord Nelson 33/1 Startup Nation 33/1 Dream It Again 33/1 Frosted 33/1 Imperia 33/1 Maftool 33/1 Unrivaled 33/1 Cozmic One 40/1 War Story 40/1 Prayers And Angles 50/1 Mr Z 50/1