Young always believed he had it in him to beat good players. What he had become less sure of since joining the senior circuit was his ability to beat bunches of them over consecutive days.
"To win back to back was a nice feeling for me. It started at [Washington] DC when I won four matches in a row at a 500 level event and beat some top-quality players."
Before bowing out to Radek Stepanek, he beat New Zealand's Artem Sitak, Jurgen Melzer, Michael Russell and Marcos Baghdatis. It was at the US Open that he formally announced his arrival among the game's elite, being beaten in the round of 16 by Andy Murray, a player he had beaten at Indian Wells earlier in the year.
The struggles of his first few years on tour seem to be behind him.
"You play men and you're just a boy. Boys against men can get rough," he says.
"You don't expect a child to come in and win games unless it's a video game, but yeah, it was a big learning curve for me."
Still, despite all the warnings, when you're winning all the time at junior level the cold reality of losing all the time can hit hard. By the end of 2007 he had played 15 matches on the full ATP Tour and had won two of them; in 2008 he won eight of 28. In 2009 he didn't win a match on tour; in 2010 just three before his breakthrough year of 19 wins and 17 losses.
"You go from being No 1 junior in the world and winning all the time to not winning at all - it's a big shock," Young says. "It definitely hurts the confidence."
Young said there were times when he began to doubt whether he was going to make it in tennis, something that seemed inconceivable when John McEnroe marked him out for stardom aged 10 after hitting up with him.
Did McEnroe's endorsement become more of a hindrance than help?
"It was great at the time, you know, when everything you get is positive. When things turned negative, that's when it starts to affect you. But sometimes you have to take the rough with the smooth, you have to take your lumps."
Young is coached by his parents, Donald snr and Ilona, and it is his mother who travels on tour with him.
"Off the court she's mum," Young says. "At the tennis site she's coach. It's a fine line. Sometimes you can get into grey areas, but for the most part she's definitely mum first."
He also has friend Calvin Kemp in Auckland, a burly figure he grew up with playing doubles in juniors but who also looks as if he could play a handy role as a bodyguard if needed.
Having been immersed in the sport since he was 3, it seems reasonable to ask whether he shares Andre Agassi and Serena Williams' apparent distaste for it.
In a recent interview Williams admitted she didn't like her job.
"It's not that I've fallen out of love with it. I've actually never liked sports and I never understood how I became an athlete," she said.
Agassi's confessional autobiography Open could have just as easily been titled "I hate tennis".
"I haven't got to that point," Young counters. "I haven't won a bunch of slams and millions of dollars. It hasn't got to the point where it's old for me.
"I still enjoy it. The travel can obviously get tough, coming from the States to here and Europe, travelling 37-odd weeks a year. But that's the job I've chosen and that's what comes with it."
Young is based in Atlanta, where his parents run a tennis school, but grew up in Chicago. Not surprisingly one of his heroes was Michael Jordan.
Whereas Jordan dominated the NBA before trying his hand at pro baseball in the Chicago White Sox organisation, Young was forced to choose between his two great sporting loves early. Predominantly a power-hitting first baseman, Young eventually picked the racket over the Louisville slugger.
As he said, tennis means travel and he's in Auckland with an immediate goal - "I want to get some matches before Australia because I've been off for a month-and-a-half" - and some more ambitious targets.
"I'd love to win my first title," he says. "Another deep run in a slam would be awesome and I'd like to get my ranking inside the top 20."
Should those goals be ticked off, it would be proof positive that the tough times are in the past.
