diamond symbol with an x
 

Somebody tell me what does the diamond symbol with an x mean? I know a circle with an x mean a race that has been taken off the turf and put on the main track, but I couldn't find an explanation for this symbol. I see it a lot in Gulfstream races.

In addition to the main dirt track, Gulfstream also has a track with an artificial tapeta surface. Many of their off the turf races are moved to the tapeta. They have found that many turf horses run better on the tapeta than on the main track. I'm only guessing, but could that symbol refer to a races moved to the tapeta?

I think you are right. Makes sense. Thanks for the help.