The seven-year-old grey showed he relishes a stamina test with a 12-length victory over three and a half miles at Haydock in November before putting up a decent effort to finish third in the Peter Marsh Chase
Hainan stayed on in the closing stages of the near three-and-a-quarter-mile contest to finish fourth behind The Dutchman. He was two and a quarter lengths ahead of Yala Enki, who won the Betfred National Trial back at Haydock last weekend.
"He won well at Haydock and ran another good race there in the Peter Marsh and finished third in the end," said Smith.
"He does seem to want an extreme trip. He jumps well enough. We're very hopeful of him, he seems to be in very good form going there."
The Bingley handler also saddles Smooth Stepper, who has won three times over the near three-mile trip at Newcastle, but Smith wonders if he will last out the extra mile on what is sure to be testing ground.
"He likes Newcastle, but obviously he's got an extra mile to go and I've a feeling the ground is going to be a bit claggy. Whether that will suit him or not for that further mile, I don't really know," she said.
"He does seem very well and both go there with possibilities."
Harry Whittington feels this is the ideal race for Vinnie Lewis, who has improved for the step up in distance to win his last two races at Sedgefield and Plumpton.
"Where he's improved so much is running him in his conditions. We've found his conditions and he's excelling," Whittington told At The Races.
"He seems to love soft, heavy ground and as far as you like. In the Sussex National it looked like he could have gone round again.
"He was awesome at Plumpton. There were some good yardsticks in there like Shotgun Paddy.
"Vinnie Lewis is sweet at the moment. We've got a very progressive seven-year-old and he's thriving.
"The Eider looks tailor-made for his next step. He wasn't stopping in the Sussex National and the extra two furlongs shouldn't be a problem."
West Of The Edge did not make the cut in 2017 but is a leading contender this time round and staked his claim with a good second to Emperor's Choice at Haydock in December.
"He's in really good form and I can't wait to run him, conditions should suit," said his trainer Dr Richard Newland.
"We've been wanting to try him over four miles for a while, we wanted to run in it last year but couldn't get in the race, he's in this year but a bit higher, obviously.
"Hopefully he'll run well but it's quite competitive, looking at it.
"We don't actually know if he'll get four miles, we just hope he will. He's always looked like he might enjoy it.
"He likes heavy ground but whether the combination of four miles in heavy ground suits, we'll know after the race."
Neil King is not concerned Milansbar went up 9lb for his victory in the Classic Chase at Warwick last month as the 11-year-old seeks to become the first horse since Willsford to also take the Eider in the same season.
"We know he stays and on a big, galloping track it should be the ideal race for him," said King.
"He's gone up 9lb but it was one of those situations that because of a disappointing season last year, he'd dropped down the weights and the handicapper is always keen to get them back up to where they were.
"He's a lovely, big, strong horse and they carry the weight."
Fergal O'Brien is hoping Chase The Spud can put a poor run in the Welsh National behind him and put himself in the picture for the Randox Health Grand National or the Midlands National, which he won last year.
"He was very good first time out at Haydock, then he was a bit disappointing in the Welsh National at Chepstow," said O'Brien.
"He schooled well on Monday. He is working well and I'm very happy.
"We will see how he gets on in the Eider and will decide from there whether go for the National or back to the Midlands National."
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