One-time Victoria Derby favourite and talented stayer Gunstock (NZ) (Tavistock) has been retired after reaggravating an old injury when he finished fourth at Sandown on Saturday.

The injury-plagued galloper only raced nine times, resulting in four victories, including the Gr.3 Norman Robinson and Coongy Handicap, both over 2000 metres at Caulfield.

“We found him to be off in his action again,” confirmed Michael Kent Jnr, who trained the son of Tavistock in partnership with Mick Price.

“After having a long discussion with the owners, we think it is in the best interests of the horse if we look after him and give him a good home.

“For him to have so many injuries, it must be a conformation issue the fact that he keeps reinjuring the same knee … he has got very fragile knees.”

Gunstock was purchased by Import Racing as a two-year-old at auction in Australia and was sent out favourite in the final race at Sandown on Saturday after returning with a win following more than six months on the sidelines.

“It’s a crying shame, I hate to think how good he could have been,” Kent Jnr lamented.

“He has reached a mark of 100 in very few starts with multiple injuries, so it speaks loudly of his class but also his courage.

“We couldn’t have done much more, he went down to the beach and we galloped him very lightly on grass tracks but he just wasn’t a very sound horse unfortunately.”