Sept. 8, 2012— -- Taylor Townsend came to the U.S. Open this week ranked as the number one junior women's tennis player in the world. But she almost didn't make it here because of her Serena-like build.
Over the summer, Townsend's trainers at the U.S. Tennis Association told her that she couldn't compete at the U.S. Open or any tennis tournament until she got into better shape.
"I didn't get any definite answer on why they didn't want me to play they just told me that they felt I should focus on my fitness," Townsend said on "Good Morning America" this morning.
"She was angry, she was upset, mad, confused," Townsend's mother Shelia Townsend, a former college tennis player, told ABC News. "She wanted to play and she didn't understand why she wasn't being allowed to."
"How would you feel if you were the best in the world and they tell you can't do what you wanted to do?" her mom asked.
Both she and her mother were left confused about what metrics the young player had to meet to be allowed to play again under USTA auspices.
"I actually asked them if they would give me some specifics so that I can help facilitate helping her to understand what they were doing and the reasoning behind what they were doing," Townsend told ABC News, as her daughter competed in the semi-finals doubles competition at the U.S. Open. "I never was able to get it."
The USTA was not "giving her any kind of specifics about whether it was that they wanted her to get to a specific weight or this amount of body fat," her mom said.
Patrick McEnroe, the general manager of the USTA's player development program told ABC News that the U.S. Open was never off limits to Townsend. He said they simply recommended she sit this one out after she struggled with her game this summer.
"No one tournament is bigger than a player's career, especially when the player is 16. Taylor continues to be one of our best prospects, and our goal is her long-term development," McEnroe said in a statement.
Now the association is saying it will reimburse Townsend for U.S Open expenses and Townsend is eager to put the incident behind her.
"I think it will pass, because I think we all have a common goal here, that I want to do well," said Taylor Townsend.
Townsend, 16, has been compared to tennis legends Venus and Serena Williams. And in January, she became the best junior women's tennis player in the world after sweeping the Junior Australian Open singles and doubles.
Her mother allowed her to move away from her family to Boca Raton, Fla., to train at the U.S. Tennis Association's development program, and eventually Sheila Townsend moved to Florida as well to be with her daughter.
After winning the Australian Championship, Taylor Townsend gave up McDonalds—all fast food in fact—and began an intense training regimen.
Townsend also took up running and weight lifting.
But that wasn't enough for the USTA which took note of her physical conditioning. Taylor Townsend is 5-foot-6 and weights 170 pounds, her mother told ABC News.
The USTA, which sponsors certain members to play in major tournaments, has initially refused to finance Taylor Townsend's entry in the U.S. Open or other tournaments.
"Our concern is her long-term health, number one, and her long-term development as a player," McEnroe told the Wall Street Journal. "We have one goal in mind: For her to be playing in [Arthur Ashe Stadium] in the main draw and competing for major titles when it's time. That's how we make every decision, based on that."
Townsend's mother put together the money herself and paid for her daughter to make the trip to the tournament.
"I just felt like with what Taylor had been doing throughout to the summer, her results, and the fact that she was number one in the world, why not?" Townsend said.
After competing in the 2012 Wimbledon Championship in July, Townsend was only allowed to compete under USTA sponsorship in one more tournament in Vancouver.
Townsend reached the semi-finals at the U.S. Open on Friday, but lost 6-4 6-4 in a tough match against Anett Kontaveit of Estonia.
She was disappointed and upset that she didn't play her best, but her mother said she was ultimately just fine.
"She was OK. She said that she didn't play as well as she wanted to play," Townsend said. "But I was proud of her."
ABC News' Tanya Rivero contributed to this report.