Gold Cup hero Sizing John ruled out of Cheltenham Festival by Harrington

Sizing John will not defend his Gold Cup crown at Cheltenham next week after his trainer Jessica Harrington revealed the 2017 winner would miss the festival.

The eight-year-old was 6-1 joint second favourite to become the first horse since Best Mate to retain his crown and Harrington described the hairline fracture to his pelvis as a massive blow.

Speaking to the Racing Post on Thursday evening, Harrington said: "Robbie [Power] rode Sizing John this morning and felt that he wasn't quite right.

"It's most unfortunate. We were very much looking forward to him going back to Cheltenham to try and win the race for the second time. He's off on his holidays now."

Watch Sizing John's Gold Cup win

Harrington is still set to be represented in the Timico Cheltenham Gold Cup by Our Duke, who is now a best-priced 7-1 and will be partnered by Power. Noel Fehily had been booked to ride last year's Irish Grand National winner, but he might yet have a ride in the race as Harry Fry is understood to be seriously considering supplementing American.

In her Unibet blog Harrington added: "He cantered as normal this morning at Commonstown and during routine checks this afternoon was found to be sore behind.

"I've had our vet Mark McRedmond come and check him over. He has found a hairline non-displaced fracture of his pelvis. He will have box rest for two weeks and then be rescanned with a view of starting walking exercise.

"This is a massive blow for the Potts family and for all our team here at Commonstown."

Might Bite has been trimmed to a best-priced 100-30 at the head of the market, with Native River an 11-2 shot and 10-1 bar.

Last year's Irish, Cheltenham and Punchestown Gold Cup winner had made an encouraging start to his 2017-18 campaign when trouncing Djakadam by seven lengths in the John Durkan Chase, but he was a disappointing seventh last time out when beaten 32 lengths in the Leopardstown Christmas Chase in December.

Sizing John joins the last two winners Coneygree and Don Cossack in not making it back to the festival to defend his crown. The 2014 winner Lord Windermere is the last horse to line up in the following year's Gold Cup.

Power tweeted: "Heartbreaking to get the call from this evening with the news the Sizing John won't return to challenge for his Gold Cup next week. We're all very disappointed but don't worry, he'll be back!"

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