Nash Rawiller says More Joyous has nothing to prove to him and can show everyone else how good she is by beating odds-on favourite So You Think in Saturday's $3 million Cox Plate.Although Rawiller says he can't find a chink in So You Think's armour, his opinion of the Gai Waterhouse-trained More Joyous is huge."I think she can (win). I'm not saying she will but I think she can," Rawiller said."I think this mare is very good and she is probably still a little underestimated."She's got to prove it

Nash Rawiller says More Joyous has nothing to prove to him and can show everyone else how good she is by beating odds-on favourite So You Think in Saturday's $3 million Cox Plate.

Although Rawiller says he can't find a chink in So You Think's armour, his opinion of the Gai Waterhouse-trained More Joyous is huge.

"I think she can (win). I'm not saying she will but I think she can," Rawiller said.

"I think this mare is very good and she is probably still a little underestimated.

"She's got to prove it. She doesn't have to prove anything to me. I ride her a lot and she's proven it to me, but basically she gets her chance on Saturday to come out and prove it to everyone else.

"I can remember the first time I got on her back in trackwork and she blew me away that morning and she hadn't even jumped out of the barriers at that stage.

"She's come a long way in a fairly short time but Saturday is the big test."

More Joyous is shooting for her ninth straight win and drew ideally in barrier three in the 10-horse field.

Rawiller has been in the saddle for seven of her 10 career wins including her last-start victory in the Toorak Hcp (1600m) in which she set a weight-carrying record for a mare when she shouldered 58kg.

The Waterhouse stable is in great form, landing its 102nd career Group One win and its fourth already this season when Descarado won last Saturday's Caulfield Cup.

More Joyous has landed two of them at her past two starts in the George Main Stakes at Randwick and the Toorak Handicap at Caulfield.

But there is a query on her not having raced beyond 1600m and having to jump up to the toughest 2040m test in Australasia.

"There is always the option of coming back to the Myer Classic (1600m), but this is the grand final of Australian racing so we've got to try and be the best on Saturday," Rawiller said.

Rawiller has ridden in seven Cox Plates with his best result being a second on the Bart Cummings-trained Wonderful World in 2007.

He has ridden Waterhouse runners in the past two years finishing fifth on Theseo in 2008 and eighth on Rock Kingdom last year, but rates More Joyous as a better chance than those horses.

Steven Arnold said he would jump So You Think out of barrier five and be "pretty positive" in the early stages of the race and if there was no pace he could attempt to lead all the way as Glen Boss did on him last year.

"If they're not going to go quick he can take it up or if something wants to go around them, then it can lead," he said.

"The only thing I can do is ride him to his strengths and have him as comfortable and as relaxed through the first half of the race. If that means he's in front, or running second, third or fourth, that won't worry me."

There is certainly no complacency in Arnold's approach and he named four rivals as possible dangers.

"More Joyous, her record is outstanding. He hasn't come up against her so she is probably the X-factor," he said.

"Whobegotyou and Shoot Out are top-class horses and I'm not taking them lightly as I'm sure they will give a good account of themselves."

Arnold has ridden in four Cox Plates and rode Zipping into third place last year to So You Think.

"He's a danger. He's as hard as nails. He's a tough weight-for-age horse and if there's any flaws in the other horses he'll be there to test them. He'll be very strong the whole way," he said.

Arnold said ideally good to dead ground would suit So You Think as he attempts to become the 13th multiple Cox Plate winner.

The track was rated a dead (4) on Tuesday morning when four Cox Plate horses - New Zealander Wall Street, Macau's Luen Yat Forever, Epsom Handicap winner Captain Sonador and Epsom runner-up Trusting - were put through their paces.