FORT WORTH, Texas -- Don't let her poker face fool you. Amanda Sakkari is trembling when she's in the player box watching her sister, Maria Sakkari, play a match. 

"I am shaking," Amanda told WTA Insider at the WTA Finals, where her older sister played lights-out tennis to qualify for Sunday's semifinals. "It's very stressful because when you see your relative suffering on the court, it's hard for me to witness that."

Amanda is four years younger than Maria, and she's had a front-row seat for her sister's rise through the rankings over the past five years. After graduating from Boston University, Amanda is now at The New School in Manhattan, where she is getting her Masters in Media Management. 

The good news for Amanda is she's a quick flight away from Maria's resurgent run through Guadalajara and Fort Worth. The bad news is she's had to juggle her schoolwork and exams throughout the week. Luckily, Downtown Fort Worth is not short of quiet coffee shops that are ideal for getting work done. 

Their lives weren't always as intertwined. Maria's travel schedule meant she was absent for long stretches of time when Amanda was younger. But it did not take long for Amanda to realize the significance of her sister's business trips. 

"It's normal not to understand," Amanda said. "After her winning more and more and seeing her on TV back home at 2:00 a.m., I realized that what she was doing was really big. 

"When fans were going up to her and screaming and chanting her name and supporting her, I think that was the moment where I realized, 'Whoa, my sister's really good at what she does.'"

"I think my role is being a distraction, to breathe in and breathe out away from the tennis."

- Amanda Sakkari

Now that they're older and have left the nest, the bond between the sisters grows stronger with every day. When she comes to tournaments, Amanda sees her role as the distractor. She's the one person who can pull Maria out of the tennis world, even if just for a few hours. 

"I never in a tournament talk about the result, or the tennis, or what time is your practice," Amanda said. "I'm more like what are we going to eat, or this is what's happening in my life, try and get her mind away from tennis because that would reduce some pressure."

"We were laughing that my role is a plant, because I don't do anything. I just exist there. I realized that this year at Indian Wells when she made the final. Not a single time did I talk about tennis. We're eating at Cheesecake Factory. I was also working."

Maria relishes the time they can share together on the road, both with Amanda and her older brother, Yiannis, who works in the UK. Maria and Amanda shared a room during Guadalajara and spent the time playing Super Mario, a hobby that they've shared together for years. 

"Her aura is very unique," Maria said. "Both my siblings are. Yiannis was with me in a couple of tournaments this year. We're very close. 

"It's just very nice to have them around. Like at Indian Wells, we would take the car and go to Whole Foods every day. That was the highlight of the day. It's very nice just to do little things."

Amanda says the personality differences between herself and her older sister have always been evident and welcome. Growing up in a tennis-mad family wasn't always easy. To this day, her grandmother watches the most tennis of anyone, and her mother, a former player on the WTA Tour, is still steeped in the sport. Amanda did give tennis a shot. It just wasn't for her.

"It was too much in the family," Amanda said. "I just wanted out. I danced for 15 years and did that as a hobby." 

Amanda credits Maria's tennis career for leading her toward a career in media, where she hopes to find her path into the film and television arena. Shadowing her sister through her media obligations, as well as rubbing shoulders with the crew and producers who have followed Maria throughout the season as part of Netflix's upcoming docuseries, has given her a chance to ask questions about the industry.

"I'm really interested in film and TV and going into the production side of that," Amanda said. "I think the Netflix stuff has inspired me. I also took film classes when I was an undergrad. That's where I see myself. I would not say no to sports, but I want to also make my own path for myself.

"In a way, my sister kind of helped me find my own path as well. We're intertwined in that way." 

WTA Finals: Sakkari dominates Jabeur to finish unbeaten in group