A girl with a robotic arm threw the ceremonial first pitch at the fourth World Series game between the Houston Astros and the Los Angeles Dodgers at Minute Maid Park on Oct. 28.

Seven-year-old Hailey Dawson was diagnosed with Poland syndrome at birth, a rare disorder that can cause underdevelopment and deformation in the hands. The defect has left her with only her thumb and pinky finger on her right hand.

Dawson uses a 3-D printed hand developed by engineers at the University of Nevada, Las Vegas. Eight versions of her robotic hand have been used since she first began pitching in the pro-circuit in 2015. On Saturday she was adorning a custom-made hand featuring the Astros logo, representing the home team.

Prior to her big throw, Hailey attended the Play Ball event at the Houston Astros Youth Academy, where she was given tips by Chicago Cubs All-Star first baseman Anthony Rizzo.

"I told her to have fun, take a deep breath," Rizzo said. "This is really cool for her, I got to play catch with her. What an inspiration. She's not going to let any disability or disease stop her. It's really cool that Major League Baseball is recognizing her and letting her throw out the first pitch."

With a few games under Dawson's belt, her mother Yong Dawson said she has big dreams involving the MLB.  

Since tossing her first ball at a Baltimore Orioles game at, Dawson hopes to throw the first pitch at all 30 major league parks.

"She doesn't get nervous," Dawson's mother said. "She's so chill. She goes right up and kind of hams it up, too. It's fun."

Along with pitching for the Astros and Orioles, she also threw the first pitch for the Washington Nations at Nationals Park in Washington, D.C. earlier this year.

"She's really a terrific young lady," MLB commissioner Rob Manfred said after meeting Dawson. "It's an honor for Major League Baseball to have her here to throw out the first pitch. It's an amazing scientific and medical accomplishment."