Grabarz had finished 2011 ranked equal 29th in the world (with 15 other athletes, two of them British) having cleared 2.29m.
This, coupled with failure to gain a world championship team place, led to his funding being cut and he considered whether to continue in the sport. The alternative for the Loughborough University sports drop-out was a living restoring classic cars.
His coach, Fayyaz Ahmed, was incensed. He told Grabarz to stop wasting his time, go away and not come back. Grabarz acknowledged he had "been wasting too much time and not applying myself", and buckled down. The outcome was a string of personal bests, the European title, and Olympic bronze. He equalled Steve Smith's 20-year-old UK record (2.37m), and first in the season-long Diamond League earned him a prize of just under £25,000. Yet he said yesterday that he may well soon be restoring a classic model – his own – bought with the proceeds of success.
"I have been shopping for a classic car," he said. "I might have just found one, but I have yet to reveal what it will be, because it's not a done deal yet."
He has carefully considered where he is going, silencing his mobile and chilling out in Queensland, as he explains.
"I went to a really small town in the outback – Theodore – with a population of a few hundred at best. Nobody recognised me on a farm of 22,000 acres and a few kangaroos."
He had five weeks off: "double what I would normally have", and has been in training for nine weeks, with some "unfinished business – I didn't win the Olympics".
The European indoor championships and the worlds in Moscow are on next year's programme, which will kick off in Glasgow with the inaugural international at the Emirates arena on January 26. Britain face the USA, Russia, Germany, and a Commonwealth Select in the first international athletics event in the new 5000-seat venue.
It will be the first GB meeting after the end of a 13-year insurance sponsorship.
It is to be hoped that UK Athletics will not see this as an excuse for penny pinching or dilution in quality. When the Kelvin Hall launched Glasgow as an international indoor venue in 1988, sponsors Dairy Crest bankrolled the US world 400m record-holder, Butch Reynolds. The new £113m stadium is depending on similar support now to help build a new reputation.We have three Olympic athletics gold medallists. Hopefully the budget will stretch to have them compete. At this early stage, world indoor bronze medallists Holly Bleasdale (pole vault) and Shara Proctor (long jump) are confirmed along with Grabarz.
The grandson of a Polish immigrant, he has emerged from obscurity in the past 12 months, and may be just the man to help cement the foundations.
Key to his improvement "was a matter of committing to my programme and not going through the motions any more – applying myself to the training".
He had no complaint about losing his funding, which has now been restored.
"You either perform and get your funding, or you don't perform and don't get the funding," he said. "It's fair enough. I am not here for an easy ride – I am here for a successful one. If I don't perform, why should people support me?"
Despite his coach being employed at his former alma mater, and his approval of "the centralised system that has worked for other sports," Grabarz won't move there full time.
"I don't think I will be training there every day. I think it will be half a week there, half a week in Birmingham," he said.
His modest 2.29m took bronze in London, but soon after he cleared 2.37, his best to date. "It's always frustrating to jump your highest after the championships," he told me, "but it was my first ever Olympics. To perform on that stage, in front of a home crowd, it was a great deal bigger than I ever thought it was going to be. I think I performed to the best of my ability. It was nice to go out and jump high afterwards, and beat the guys who beat me at the Games."
Something of an exhibitionist, posing naked for a gay magazine and posting a photo of himself naked on Twitter, with his medal and a strategically positioned Union Flag, there was reason to think he might follow US Olympic finalist Jamie Nieto, or his coach, into acting.
Nieto starred as an FBI agent in the film Jerusalem Countdown, while Ahmed has had bit parts in EastEnders and The Bill.
"That's not for me," said Grabarz. "High jump is a big enough stage, and that's all I am keeping it to."
Pressed in previous interviews as to whether he is gay, he said: "I like to be slightly mysterious, or at least have people think I am. So yeah, if it gets them talking that's really cool. I'm excited by the fact that people might think I'm gay."
He knows that when he cleared 2.37m, "there was more in the tank. I'm definitely hoping to improve. The big number in high jump is 2.40. I'll not really do myself justice until 2.40, and the way I was clearing some bars in the summer, I know I can go higher than that."
Grabarz, who in October turned 25, may feel his best is ahead. Yet only seven men have cleared 2.40m outdoors (world best: 2.45, by Cuban Javier Sotomayor, 1995) and the last was 12 years ago. Time may already be running out. The oldest member of the outdoor 2.40 club was 26.
Tickets for the 2013 British Athletics Series are available at www.uka.org.uk