The David Hayes stable has suffered its second blow in as many days after imported galloper Our Aqaleem was injured at trackwork at Flemington on Thursday.

The Hayes camp was rocked by the sudden death of another import, Changingoftheguard, who died after complications developed during a routine gelding operation midweek.

Our Aqaleem was working at half pace over 1600 metres when jockey Steven Arnold heard a loud crack from the six-year-old's shoulder.

Hayes stable foreman Bruno Rouge-Serret said Arnold immediately dismounted the son of Sinndar and called for assistance.

"He didn't complete his work," Rouge-Serret said. "He was about half-way through when it happened. There was no fall or anything like that. Steven just got off him when he heard the noise.

"It looks like he has a should injury. The horse is pretty lame at the moment and I'd have to say he'll miss the Australian Cup."

Rouge Serret said Our Aqaleem was taken the Werribee Vet Clinic for x-rays and further assessment with the stable holding fears for the stallion's life.

"We are waiting for what they say at Werribee," Rouge-Serret said. "Hopefully he'll be okay and will make a recovery but he won't be running on Saturday."