Unique Bella, the champion female sprinter of 2017, was retired on Saturday after she emerged from a workout at Del Mar with a sesamoid injury, according to Fabricio Buffolo, the executive director of Don Alberto Farm that owns the popular 4-year-old filly.

The injury is not severe, Buffolo said.

Unique Bella, 4, won 9 of 12 starts and earned $1,272,400. She won eight stakes, the most recent of which was the Grade 1 Clement Hirsch Stakes at 1 1-16 miles for fillies and mares at Del Mar on July 29.

An article with comments from Buffolo and a glance at Unique Bella's career will appear on DRF.com later this afternoon.