Donald Young finally steps out of boys zone

Donald Young, who has spent six years becoming an American overnight sensation, finally came of age at the US Open on Sunday.

The 22-year-old reached the last 16 of a Grand Slam for the first time when he defeated experienced Argentine Juan Ignacio Chela 7-5, 6-4, 6-3.

But it has been a long, tough road for Young, who finished 2005 as the world's top junior at 16 years and five months, the youngest boy ever to do so, and who won the 2005 Australian Open boys' title and 2007 junior Wimbledon.

Until the US Open, his 2011 high had been beating world number four Andy Murray at Indian Wells before gaining notoriety for a profane tirade on Twitter against the US Tennis Association (USTA) after feeling slighted for a French Open wild card.

Young apologized and now is happy to do his talking on the court.

"At times I wasn't winning matches at Challengers and I was losing to guys 300 in the world," said Young.

"To go from losing a first round Challenger in Aptos, California, to the Round of 16 of the US Open is great. But you have your highs and lows in tennis. I've definitely had the lows. Hopefully I'll have a lot more highs."

Young had made the third round at Flushing Meadows in 2007 when, playing on a wildcard, he eventually fell to Spain's Feliciano Lopez.

But his failure to push on from there left his supporters and detractors frustrated and, once again, the Atlanta player, with a ranking of 84, needed a wildcard from the USTA, once the target of his derision, to get to the US Open this year.

Young believes he has been steadily showing signs of progress since he changed his attitude both on and off the court, helped by a winter in Los Angeles hitting with Mardy Fish and Pete Sampras.

"I wanted to do something different. All the off seasons I've spent a week or two training and then at home just kind of having fun. I could have trained harder at home, but I didn't," he admitted.

"So to take me away from home and I was actually there by myself. So to do that was really different, to be by myself every day to get up and eat breakfast at the same time and go work out. It was great."