Keeneland Race Course in Lexington, Ky., has become the latest horse-racing track to announce that it is replacing its synthetic surface and returning to dirt.
The Polytrack surface will be discarded after the end of the April meeting, replaced by a dirt surface for the fall. The Polytrack was installed in 2006.
Del Mar plans to replace its Polytrack with dirt after this summer's meeting. Santa Anita previously switched back to dirt.
Several tracks had switched to synthetic surfaces with the intention of improving safety for horses, but statistics have been mixed about whether those surfaces produced a major improvement in safety.