Kauto Star was a winner by eight lengths

Coming to the last fence well clear of the rest of the field, the 8-13 shot struggled to get over but somehow managed to land safely and win.

Ruby Walsh's mount, trained by Paul Nicholls, had also recovered from a bad mistake at the fourth last fence.

Exotic Dancer, ridden by Tony McCoy, edged out Racing Demon and Timmy Murphy for second.

Interview: Kauto Star's trainer Paul Nicholls

Ollie Magern set a strong pace for the first mile before Monet's Garden took up the running.

Although Tony Dobbin tried to stretch the field down the back straight, Kauto Star, Racing Demon and Exotic Dancer were all waiting to pounce.

After his mistake with four to go, Kauto Star recovered superbly and looked a class act as he accelerated getting to the second last.

He's a machine. I've never ridden a horse like him Jockey Ruby Walsh

Having now won the King George and the Betfair Chase, victory in the Cheltenham Gold Cup will land a £1m bonus and he is a best price of 2-1 to win at Prestbury Park in March.

Winning jockey Walsh was delighted with the horse's success.

"He has to be one hell of a horse to do that after missing the fourth-last and the last as well," he said.

"I thought I'd just let him pop the last and he just came up out of my hands, but he's won easy.

"He's a machine. I've never ridden a horse like him and it's a privilege to ride him."

Nicholls added: "He wasn't concentrating. There's the big crowd and the big screen and he's just taken his eye off it. He just stepped at it, but he never looks like falling.

"His best round of jumping was at Haydock when we just dropped him in. Today we couldn't do that but he kept galloping and it's good for him and for the whole team to get it over and done with."

Ungaro has made a good start to his chase career

Earlier, the well-fancied Straw Bear was easily beaten by fellow Irish challenger Jazz Messenger in the Christmas Hurdle.

Ridden by Grand National-winning jockey Niall 'Slippers' Madden, the 10-1 victor, trained by Noel Meade, is the third Irish-trained winner in a row in the race after Feathard Lady last year and Harchibald in 2004.

The pace-setter Afsoun came to grief fell four fences from home leaving Jazz Messenger in the lead.

606 DEBATE: Your views on the day's races

Straw Bear, ridden by Tony McCoy, challenged on the turn for home but never looked like getting past the leader.

Noble Request also came through to challenge but Jazz Messenger held on for victory.

Meanwhile, Ungaro claimed a comfortable win under Mick Fitzgerald in the Feltham Novices Chase to give the jockey his third win in the race.

Although Fitzgerald's mount made a number of errors during the race, he recovered well in the latter stages and the pair safely jumped the last to run clear of Boychuk.

The well fancied Yes Sir was a big disappointment

King George VI Chase
1. Kauto Star (R Walsh) 8-13 Fav
2. Exotic Dancer (A P McCoy) 9-1
3. Racing Demon (T J Murphy) 7-1
9 ran

Christmas Hurdle
1. Jazz Messenger (N P Madden) 10-1
2. Noble Request (R Johnson) 7-1
3. Desert Quest (R Walsh) 8-1
7 ran