Ollie Magern, owned by Roger Nicholls, from Milcombe, near Bloxham, is lame and will miss the John Smith's Grand National on Saturday.

Trainer Nigel Twiston-Davies discovered the problem on Wednesday, and scratched the ten-year-old from the Aintree marathon.

Although the injury is not serious, Ollie Magern is unlikely to run again this season.

Twiston-Davies said: "He has had those problems in the past, but he had been much sounder this season. Now it's happened just a few days before the National.

"I don't think we'll run him until next season now."

BLACK Jack Ketchum has been retired after trainer Jonjo O'Neill revealed the former top-class performer "wasn't enjoying it anymore".

The nine-year-old won his first eight starts.