Sizing John strikes with authority for Cheltenham queen Harrington

In a week when Douvan misfired for a first time, Sizing John seized the opportunity to step out of his nemesis's shadow in spectacular style with a famous Timico Cheltenham Gold Cup triumph for Jessica Harrington and Robbie Power.

Harrington, with her first runner in the race, struck gold as Sizing John travelled like a dream and jumped with all his usual fluency to score by two and three-quarter lengths from Minella Rocco, with Native River a short head behind in third.

"I can't believe it," said an emotional but admirably composed Harrington, who this week became the most successful female trainer in the history of the festival, ahead of Jenny Pitman.

"It's unreal. He was absolutely amazing the way he jumped and travelled. Robert said he wasn't going around the inside, and then he did. He was the first runner I had in the Irish Gold Cup at Leopardstown and he won that, and now he's done it again. It must be beginners' luck."

In a dramatic race, there was a key moment at the third last, where Cue Card fell for the second year in a row, and another at the second last as Sizing John capitalised on a blunder by 3-1 favourite Djakadam to forge into a clear lead.

Power had tracked the Ruby Walsh-ridden two-time runner-up for most of the race and still looked to have plenty left in the tank as he went to the front, but the punishing final climb in the 3m2½f showpiece was unknown territory for Sizing John.

The three miles he had negotiated successfully in the Irish Gold Cup was as far as he had gone before, but any doubts about his stamina were laid to rest as he surged home for an emphatic success. With this triumph, Sizing John became the first horse since Imperial Call in 1996 to win both races.

"He galloped the whole way up the hill," an elated Power said after soaking up the cheers and applause of the 70,160 crowd.

"Most good Gold Cup winners have Grade 1 form over two miles, and he had that. He was third in a Supreme Novices' and second in an Arkle. Fox Norton was third in the Arkle he was second in, so I don't think anyone could say it was a bad Arkle.

"The plan was to keep out of trouble," Power added, "but I followed Ruby most of the way down the inside and got a dream run round. I thought going to the second last I had Ruby covered, and one thing about him is you can rely on his jumping.

"He winged the last and is just a very good horse. A lot of things had been going bad this season – I've had trouble with my eyes and my back – so I'm going to enjoy this day."

Minella Rocco plugged on gamely from the rear to confirm the form of last year's National Hunt Chase by denying Native River the runner-up berth. Djakadam faded into fourth, while Cue Card returned to the stables safely after his fall, although he had looked under pressure at the time.

This, though, was all about Sizing John, who secured the £327,462 winner's prize with an authoritative performance.

Harrington, who ended the week with three winners, completed the triple crown of Gold Cup, Champion Chase – which she won twice with Moscow Flyer – and Champion Hurdle, which she landed with Jezki in 2014.

On the thrill of adding the sport's blue riband contest to her already extensive CV, Harrington said: "They're all fantastic. At the time, in the moment, they're the most fantastic things. To have a winner here at Cheltenham is amazing, but this is the jewel in the crown. As long as I've been watching racing it's a race I'd dreamed of winning, so to do it is special."

Sizing John, like Wednesday's Coral Cup winner Supasundae, wears the colours of Alan and Ann Potts, who had removed both horses from Henry de Bromhead's yard in the autumn, when they severed their ties with their long-standing trainer, and sent them to Harrington.

De Bromhead had the consolation of Special Tiara's Champion Chase triumph, but this was a day that saw Harrington's status as the queen of the Cotswolds gloriously confirmed, underlined further when Rock The World and Power claimed the concluding Grand Annual.

"Sizing John's real forte is the fact he jumps incredibly fast, and in the early part of the race you could see he was gaining a length or two at every fence. He winged the last two fences – he wasn't like a tired horse," Harrington said.

"When the horses came from Henry I was very lucky to get Supasundae and Sizing John – two lovely horses that had Grade 1 potential."

Harrington gave Power much of the credit for the decision to step Sizing John up in trip. Power landed the Grand National on Silver Birch in 2007, but he came into this week with just one festival win to his name.

"It's unbelievable," he beamed. "I was only 25 when I won the National and I thought I was going to win everything in racing; when you're 35 you're not so confident! You appreciate it a bit more, and this is something that will stay with me forever."

JESSICA HARRINGTON'S 11 FESTIVAL WINNERS

1999 Space Trucker Grand Annual
2002 Moscow Flyer Arkle
2003 Moscow Flyer Queen Mother Champion Chase
Spirit Leader County Hurdle
2005 Moscow Flyer Queen Mother Champion Chase
2007 Cork All Star Champion Bumper
2011 Bostons Angel RSA Chase
2014 Jezki Champion Hurdle
2017 Supasundae Coral Cup
Sizing John Gold Cup
Rock The World Grand Annual

Gold Cup result and analysis