Dashing Wellington Steeplechase winner Rangatira has injured a tendon and will be out of action for 12 months.
The rising 11-year-old turned on one of the most spectacular jumping displays seen in years when he led all the way in last Saturday's Trentham feature, scoring by 14 1/2 lengths.
But any hopes that Stratford hobby trainer Steve Gulliver had of defending Rangatira's Great Northern crown in September evaporated when he was favouring a leg the following morning.
Gulliver had the leg scanned last Monday when a 5mm tear in the tendon was detected.
''Any tendon injury is a major but they say it's not the worst they've seen,'' Gulliver said yesterday.
''He'll need 12 months off, and will have to be confined to a box for the next three months, but it's worth doing because he's so good - he's easily the best horse I've had in 30 years - and he loves jumping, thrives on it.''
Gulliver will take Rangatira to a vet clinic at Te Rapa tomorrow where the horse will have platelet rich plasma therapy to promote better and faster healing of the injury, treatment which has become popular in recent years with a number of standardbred stars like Carabella.
Gulliver said he is keen to do anything to improve the horse's chances of making a comeback - the last horse he tried to rehabilitate after a tendon injury went amiss three years in a row.
''But I'll get all the instructions from the vet on what to do and we'll keep scanning his leg and won't bring him back until they tell us he's 100 per cent.
''With a bit of luck we'll be able to get him back. He's not a big, heavy horse, so that will be a help.''
Gulliver said Rangatira had never had tendon problems in the past.
''But these things happen. I can see how he could end up with something like this the way he rips into his fences, but it's still bloody disappointing for me and everyone else. We were really looking forward to having another crack at the Northern.''
Gulliver, 51, took over Rangatira in 2012 when he was virtually retired as a meagre three-race winner on the flat, but turned him into a fast, free-going jumper, winning four steeplechases.
Rangatira had three big paydays this season, banking $60,000 for winning the Great Northern Steeplechase, $30,000 for running second in the Great Eastern at Oakbank in South Australia and $43,000 for his win at Trentham.
Those feats this week earned him a nomination for Jumper of the Year at thoroughbred racing's annual awards ceremony in Hamilton on August 14.
His rivals are Wellington Hurdle winner Just Got Home, last Sunday's Australian Grand National Hurdle winner Sea King and Waikato-Hawke's Bay Steeplechase winner Palemo.