Races 9 and 10 at Laurel Park on Sunday, a pair of turf sprints, were moved to the main track prior to race 6.
Turf sprints are especially hard on the course. Race 7, a one-mile contest, remains on the grass.
The course was listed on Equibase as "good" for race 1 but downgraded to yielding for race 2. The course has been slow to dry following a very rainy September and some sort of precipitation or heavy dew most days this month. There was light precipitation in the area Saturday night.
The Rainbow 6, which began on race 5, is a refund because more than one leg of the wager had a change in surface.
Since the announcement was made before race 6, the late pick five is not affected.
Sal Sinatra, the president of the Maryland Jockey Club, said a rules request has been made to the Maryland Racing Commission that would make future surface changes in the Rainbow 6 "all win" races rather than force a refund if more than one leg is moved from turf to dirt.