HOUSTON -- Earlier this year, Hailey Dawson was determined to convince every Major League team to let her throw out a ceremonial first pitch at their ballpark. By the time her day was complete on Saturday, she crossed another stadium off her list, doing so on the biggest stage imaginable.
The Astros and Dodgers played Game 4 of the World Series at Minute Maid Park on Saturday -- which Los Angeles won, 6-2, to even the Series at two games apiece -- but before it started, Hailey was the star of the show. She probably couldn't have imagined that the World Series would end up being on that check list, but once Major League Baseball caught wind of her story, they jumped at the opportunity to include her in the Fall Classic.
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"I'm really, really excited," Hailey said.
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And there she stood in front of 40,000-plus fired-up Houston fans in the moments leading up to Game 4, clad in a bright orange Astros jersey with her name on the back, tossing the ceremonial first pitch to All-Star second baseman -- and possible American League MVP -- Jose Altuve. It was an incredible way to cap off a once-in-a-lifetime day for Hailey and her family, who spent the afternoon leading up to the pitch hanging out with baseball royalty.
Hailey, who hails from Henderson, Nev., was born without a right pectoral muscle due to a lack of blood supply during the sixth to seventh week of gestation. The condition, called Poland syndrome, has resulted in her missing three middle fingers, and she has an underdeveloped thumb and pinky finger.
"She's really a terrific young lady," said Commissioner Rob Manfred after meeting Hailey at a Play Ball event prior to Game 4. "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."
Hailey's condition has not held her back. Hailey, an avid baseball fan, uses a robotic hand, built initially by the College of Engineering at the University of Nevada, Las Vegas. She received her first Flexy Hand II in October 2015.
Since then, she's used eight hands, including a specially made World Series version that she used to throw the first pitch before Game 4 on Saturday. This one contained an Astros logo, as a nod to the home team.
Back in 2015, Hailey threw out the first pitch at an Orioles game, and earlier this year she did the same at Nationals Park, even getting a chance to hang with Bryce Harper, one of her favorite players and a fellow Las Vegas native.

Hailey and her family -- dad Greg, mom Yong and 13-year-old brother Zach -- were given a special behind-the-scenes tour prior to Saturday's pitch, including a visit with Houston pitcher Justin Verlander, who presented both kids with special Under Armour cleats with the inscription "Vegas Strong."
Verlander also signed Hailey's robotic hand and asked her for some tips on how to pitch. She said she would do it underhand style.
"Sometimes, you just have to figure out how to throw it to home plate," Verlander said. "I like the underhand idea."

The next stop was a visit with all-time saves leader Mariano Rivera, who was in Houston to present the Relievers of the Year Awards, along with former closer Trevor Hoffman.
"I heard you're going to throw the first pitch today?" Rivera said to Hailey. "Can you teach me how to pitch? I guarantee you, Hailey, you can teach me something."
"Mr. Rivera used to throw the cutter," Greg Dawson said to his daughter. "Only a little bit," Rivera responded with a laugh.
• Watch Hailey Dawson throw out the ceremonial first pitch
The final pregame stop was on the field to meet former Red Sox infielder Kevin Millar and his "Intentional Talk" MLB Network co-host Chris Rose. By the time it was her turn to walk out to the field to throw the first pitch to Altuve, Hailey looked relaxed, excited and up to the task.
"She doesn't get nervous," Yong Dawson said. "She's so chill. She goes right up and kind of hams it up, too. It's fun."

Prior to her arrival at Minute Maid Park, Hailey attended the Play Ball event at the Houston Astros Youth Academy, where she got to spend time with Manfred, Cubs All-Star first baseman Anthony Rizzo and MLB youth softball ambassador Jennie Finch.

Rizzo warmed her up so she would be comfortable throwing the first pitch, and she threw a bounced fastball by him as he took a big swing and miss with a plastic bat. Then he signed her 3-D printed hand, just as Altuve did after the first pitch.
"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."
Astros chairman Jim Crane, who was also in attendance at the Play Ball event, marveled at Hailey: "It just says anybody can recover from a disability and be productive, and we're just glad to have her doing it. It's a big testament to her and gives kids a lot of incentive to get out there and play ball."

The Game 4 pregame ceremony included an anthem performance by the Houston Police Department Quartet, who also presented the nation's colors. Astros legend Roy Oswalt, who pitched the pennant-clinching Game 6 in 2005 and was named the MVP of the National League Championship Series, delivered the game ball. He was accompanied by Paris Jackson of the Boys & Girls Club of America.

Modern Family star and Houston sports superfan Rico "Manny" Rodriguez, called "Play Ball!" as the final act of the Game 4 pregame festivities.