Valeria Reyes-Chian can divide her opponents on the tennis court into two types: Those who think they will win handily, and those who feel bad and take it easy on her.

To the Chantilly freshman, it doesn’t much matter which sort is standing across the net from her. Or that Reyes-Chian is not standing at all, but playing from a wheelchair.

Born with spina bifida — a developmental disorder in which the backbone and spinal canal do not close before birth, which affects her ability to balance and hold herself up — Reyes-Chian has a more relaxed mentality for her matches.

“I just come here and try to have fun,” she said.

It is a grateful attitude from a 14-year-old who never expected to play a varsity sport in high school, who six years ago struggled to even make contact when she first picked up a racket and ball, yet found an outlet nonetheless.

“Before I started tennis, I thought I would never do anything in life and I would just be there sitting doing nothing,” she said. “But when I started tennis, I was like, I’m going to get good at this. I’m going to keep on doing it and getting better.”

On the court Reyes-Chian is, of course, a rarity. While other players tuck spare tennis balls into the sides of their skirts, Reyes-Chian slides them into the spokes of her wheelchair. A routine shot that demands just a side step and forehand from able-bodied players sometimes results in tugging, pulling, spinning choreography for Reyes-Chian. During matches, she is allowed two bounces to get to the ball instead of the traditional one.

While the Maryland Public Secondary Schools Athletic Association changed its bylaws in 2010 to accommodate athletes with disabilities by creating corollary athletic programs, the Virginia High School League has no such legislation. So Reyes-Chian competes with the Chantilly varsity, and Fairfax County has made adjustments to better accommodate her. Small asphalt ramps were built at the entrances to the school’s larger tennis court, and Chantilly Coach Karen Kegerreis and an activity bus driver underwent training for operating a bus with a wheelchair lift.

In many ways, though, Reyes-Chian is treated no differently from her teammates. She beat out 10 girls for one of the 16 spots on the team, according to Kegerreis. She goes through warmup lines and stretches with the team. She cheers on her teammates during matches — only the top six singles and top three doubles matches count toward the team score — and displays the same competitiveness on some points during her own exhibition matches as the Chargers’ top-ranked players.

“I truly think that once you get on the tennis courts, it kind of evens out the playing field,” Kegerreis said. “It’s the court, it’s the racket, it’s the lines, it’s the tennis ball. . . . That’s what’s exciting to her, you’re out and you’re competing no matter what your handicap is.”

Reyes-Chian was born in Lima, Peru, but her family moved to the United States when she was just a few months old to seek better treatment for her condition. The disability affects Reyes-Chian’s balance and leg strength, she said. She uses a walker for short distances at home and a wheelchair for longer distances and in school. Reyes-Chian also has a specialized wheelchair for tennis, with angled wheels that allow her to turn more easily.

When she was 9 years old, Reyes-Chian attended a picnic held by her rehabilitation hospital. At the event, Brenda Gilmore, a wheelchair tennis player who coaches for the Prince George’s County Tennis Education Foundation, was teaching wheelchair tennis. Reyes-Chian said she struggled to even hit a ball while stationary, but she continued to practice every Saturday with Gilmore’s team in Upper Marlboro.

The sport’s popularity grew in her household. Her father, German Reyes, watches tennis at home when he is not attending his daughter’s matches. Eventually, Valeria’s older sister, Maria Reyes-Chian, also began to play the sport with other able-bodied players on Gilmore’s team.

“I would start playing with her,” said Maria, now a sophomore and one of the top players for Chantilly. “And I think that was just a great experience. It’s a different bond we have.”

Valeria Reyes-Chian competes in the ‘C’ Division of the United States Tennis Association’s wheelchair division, playing in about five tournaments every summer. This fall, she competed for the first time in USTA Junior Team Tennis, partnering with an able-bodied teammate and playing against mostly able-bodied players as she prepared to try out for Chantilly’s team in the fall.

Valeria Reyes-Chian has continued to improve. She said her forehand is definitely the strongest part of her game, but rolled her eyes when she was complimented on her serve.

“I don’t like it how people sometimes underestimate her,” said Chantilly sophomore Michelle Tran, who sometimes plays doubles with Reyes-Chian. “She’s good, and she surprised people often. She always tells me, ‘Michelle, if you don’t get it, I’ll get it.’ That’s her thing.”

Her biggest deficiency, Reyes-Chian said, is her movement. That is getting better as she gets stronger and more fit while playing for Chantilly. Competing on the high school team provides other positives, as well, lessening to a degree the jealousy she has felt toward those without a disability.

“The biggest thing it gives her is she feels more secure,” German Reyes said in his native Spanish.

Last Tuesday in an exhibition match against Oakton, Reyes-Chian oozed that confidence. She decided the first set of a doubles match with a cross-court backhand that skidded just inside the sideline. On another point, she got to a ball late that surprised her already-celebrating opponents.

Reyes-Chian moved to the net to clear up the mistake with the confused Oakton players.

“You celebrated a little too early,” she said, a smile spread wide across her face.