Four-time group one winning mare Mosheen has been retired after fracturing a hind leg in the Tristarc Stakes at Caulfield on Saturday.

Trainer Robert Smerdon says the injury should have no impact on Mosheen's stud career which will begin in the new year when she goes to Japan's leading stallion Deep Impact.

Mosheen fractured a the tibia of her near-side hind leg which helps explain a run that by her high standards was slightly disappointing behind Streama.

A group one winner in both Melbourne and Sydney, Mosheen scored her most impressive win the Randwick Guineas last autumn, a race in which she beat the males with authority and class.

Mosheen was purchased at the 2009 Inglis Easter Yearling sale for $250,000 by her first trainer Leon Corstens.

She was later transferred to Smerdon and in January this year a 50 percent share in her was sold to leading Japanese racing identity Katsumi Yoshida who raced the 2006 Melbourne Cup winner Delta Blues.

Along with his brothers, Yoshida operates Japan's biggest thoroughbred stud, Shadai Stallion Station.

It is to Shadai on the northern Japanese island of Hokkaido that Mosheen will be sent in January to be served by Deep Impact to northern hemisphere time.