Upsets were prominent on Tuesday's Blue Grass Day undercard at Keeneland, the biggest being Positano Sunset's 14-1 surprise over the favorite Emery in the $623,338 Madison (G1) for fillies and mares.

A days-long wet weather system forecast to affect central Kentucky this weekend could wreak havoc on Keeneland's signature program of the spring meet on Saturday, in particular the two stakes scheduled for the turf.