Jockey Ruby Walsh is hoping to be fit again in time for Punchestown Festival after injuring his leg in a fall at Cheltenham.
The 38-year-old Irishman had only come back from nearly four months out with a broken leg before aggravating the injury when Al Boum Photo fell on the second to last fence in the RSA Chase.
Cheltenham Festival’s all-time leading rider has now been ruled out of the Grand National.
He spoke to Racing UK: "It's a very similar fracture on the inside of the original one, which has opened up.
"The prognosis could have been a lot worse and I just have to treat this as just another setback.
"I am determined to get back in the saddle for Punchestown [24-28 April] and hopefully finish the season on a high."