Fallbrook’s Emily Deming first attended the tournament now known as the USTA Billie Jean King Girls 16s and 18s National Championships to cheer on her sister and even act as her warmup partner.

It’s been five years since older sister Julia last competed in the event, and now 15-year-old Emily figures to be a top contender in the 16s division of the tourney headquartered at Barnes Tennis Center from Saturday to Aug. 14.

Emily this week is ranked 32nd nationally in the 18s and 23rd in the 16s. Rather than vie in the 18s, she has opted to return to the 16s for this tourney.

“I didn’t really consider the 18s as an option,’’ said Emily, who receives a first-round bye as the 15^th seed in the 256-player field. “I knew that I wanted to play the 16s, and hopefully get the wild card into the junior U.S. Open (for winning the tourney). I knew a lot of tough competitors in the 18s would be playing, and even in the 16s, there are some really good girls. I’m really just excited for the competition.’’

Support will come from her youth coach, who happens to be her older sister. Julia recently competed her collegiate career at the University of Kansas with All Big-12 academic honors as well.

“I loved coaching her,’’ said Julia, set to pursue her master’s degree at Kansas next school year. “I was very fortunate that Emily listened and was a very hard worker. She respected my opinion, and she has a great attitude and an incredible work ethic.’’

In terms of playing style, though, the sisters offer quite a contrast.

The 5-foot-4 Julia, now a recreational player, relies more on finesse with slice and spin shots. On the other hand, her little sister, pushing 5 feet in height, packs some powerful shots even as a petite player.

“Emily has a lot of tools,’’ Julia said. “But she loves being in the back, just hitting the ball hard.’’

It’s how Emily likes to take charge.

“I definitely like to put players on the defense right away,’’ Emily said. “Both of my sides are pretty strong, but definitely the backhand sets up the points.’’

In last year’s tourney, Emily reached the round of 64, placing her in the top quarter of the field.

“I wasn’t really satisfied,’’ Emily said. “I knew that I could have performed better and gotten further into the tournament. My mentality has changed a lot from that tournament. I have definitely have improved improved mentally and (upgraded) my game as well.’’

With Julia as her inspiration, Emily started playing tennis with a miniature Sponge Bob racket at age three. She graduated to a regulation racket within two years and eventually started reaching junior tourney finals at age 10.

Emily is now going into her sophomore year in high school through a home-school program called Connections Academy, which she has done since first grade.

In recent months, Emily has been coached by Steve Adamson at the Barnes Center, where she regularly practices. Also, in the last year, she has placed increased emphasis on fitness with workouts on and off the court.

Emily is exploring college choices, but it’s still early to formulate plans. While college coaches abound at this tournament, she’s putting her focus on the court.

“I learned a lot from the year before,’’ Emily said. “Now it’s just playing my game.’’

Of course, she can count on some sisterly support.

“I have to pay back the debt,’’ Julia said. “She was at every single one of my matches cheering me on, so whenever I have the opportunity, I try to help her out as much as possible. I really enjoy it.’’

So Emily definitely has a warmup partner ready.

Junior tennis nationals

What: USTA Billie Jean King Girls 18s and 16s National Championships.

When: Saturday through Aug. 14

Where: Barnes Tennis Center, main site. Balboa Tennis Club, USD and San Diego State, satellite locations (Saturday through Tuesday).

Brackets: Both divisions include 256 singles players and 128 doubles teams.

Local watch: Back in the 18s are two incoming college freshmen, Carlsbad’s Katie Codd (Duke) and San Diego’s Kaila Barksdale (Utah). Each reached the third round last year. Also vying is prep senior Katherine Hui, who has committed to Princeton. She made her tourney debut in 2018 at age 13 in the 16s. Seeded in the top 10 are Hui (eighth) and Codd (ninth). Making repeat appearances in the 16s are Fallbrook’s Emily Deming and San Diego’s Alyssa Ahn, Claire Zang, and Elena Zhao. All but Zang advanced to the Round of 64 last year. The 14-year-old Zhao is entering high school this fall. The top 20 seeds include Ahn (ninth), Zang (14^th) and Deming (15^th).

Noteworthy: Renee Brantmeier, of Whitewater, Wis., holds the top seed in 18s after reaching last year’s final. She is looking to add the 18s title to the 16s crown that she won three years ago.

Changes: The 16s finals move to the final day to join the 18s final on the schedule. This is tourney’s second year following cancellation due to the pandemic in 2020.

Spectators: Admission and parking at free at the Barnes Center and Balboa Tennis Club. Campus parking fees apply at the two universities.

Top prize: The 18s champion receives a spot in this year’s U.S. Open women’s draw.

Recent grads: Sofia Kenin, the 18s champion in 2015, won the 2020 Australian Open. Coco Gauff, an 18s semifinalist in 2018, advanced to this year’s French Open final following a quarterfinals appearance in that tourney two years ago. Amanda Anisimova, an 18s semifinalist in 2016, topped Gauff at Wimbledon in the third round this year. Two years ago, Anisimova reached the French Open semifinals.

Television: CBS Sports Network, 18s singles semifinals, noon, Aug. 13; 18s singles final, Aug. 14, 3 p.m.,

Online: ustagirlsnationals.com

Thien is a freelance writer.