Retiring 19-time champion jockey AP McCoy has said he is "very likely" to ride favourite Shutthefrontdoor in his final Grand National on 11 April.
McCoy, 40, prefers last year's Irish National winner, trained by Jonjo O'Neill, to Cause Of Causes.
The Northern Irishman said he will retire at Sandown on 25 April if he does not win the National at Aintree.
"I had some thoughts about Punchestown the following week, but I won't be riding there," he told The Times.
"If I don't win it [the National], I'll go on until Sandown. It's the end of the British season and they have been good enough to name a race after me."
Shutthefrontdoor is around 8-1 favourite for the big Aintree race, while the Gordon Elliott-trained Cause Of Causes is 20-1.
"I'm very likely to ride Shutthefrontdoor but I won't commit finally until close to declaration time [9 April] - there is plenty of time yet for something to go wrong," said McCoy.
"I'm not sure he should be such a short price, and it's a long time since he ran, but something would have to happen for me to switch from him."
Other Grand National news
Jason Maguire - Jockey will miss the National for the second year running because of injury. The 34-year-old, who won on Ballabriggs in 2011, is out for the rest of the season with a back injury,
Across The Bay (50-1) - Trained by Donald McCain, for whom Maguire is stable jockey, the horse - who was unfortunate to be carried out when running well last year - is to be ridden by Henry Brooke.
Pineau De Re (25-1)- Last year's winner, trained by former GP Richard Newland, will be the mount of Daryl Jacob, who steps in for the 2014 victor Leighton Aspell.
Many Clouds (25-1) - Aspell is set to partner the Hennessy Gold Cup victor after trainer Oliver Sherwood decided to run the horse at Aintree following his sixth-placed finish in the Cheltenham Gold Cup.
The Rainbow Hunter (66-1) - Trainer Kim Bailey reports the horse on track, with in-form jockey David Bass booked.