Editor's note: This story was originally published on June 5, 2019. It has been updated after Thursday's news that Flores' bout against Josec Ruiz has been elevated to the main event. The bout between Jose Pedraza and Mikkel LesPierre was canceled after LesPierre's manager tested positive for COVID-19.

The Top Rank on ESPN card in Stockton, California, on May 4, 2019, was headlined by two world titleholders, Jerwin Ancajas and Artur Beterbiev, but it was lightweight local sensation Gabriel Flores Jr. who was responsible for packing the house with more than 11,000 fans.

Flores didn't disappoint, thrilling the hometown crowd with a highlight-reel third-round knockout of Eduardo Reis at the Stockton Arena to stamp his arrival as a bona fide prospect.

Flores is back in the ring on Thursday for a 10-round junior lightweight bout against Josec Ruiz. The bout was elevated to the main event after Mikkel LesPierre's manager tested positive for COVID-19 and his fight against Jose Pedraza was canceled.

A fair bit has already been written about Flores and his mother, Juanita Maldonado, who was shot and killed in 2013 while attending a birthday party in Stockton. It's a story that will be told many more times as his career develops and his legend grows.

Despite that tragedy hanging over Flores' life, his father, Gabriel Flores Sr., who also trains and manages his son, remains the constant in his life.

Flores Jr. recalled watching his older brother, Rogelio Gutierrez, training with his father in their garage as a kid. That was his introduction to the sport.

"I was amazed by it," Flores Jr. said. "I liked watching so much, I didn't run around. I just stayed in the garage watching the whole time so that I didn't get kicked out."

A poster held up during the May 4 fight between Gabriel Flores Jr. and Eduardo Reis in Stockton, California, shows a childhood photo of Flores and his late mother. Mikey Williams/Top Rank

In elementary school, when he got an assignment to write about what he would like to be when he grew up, his answer was always the same: boxer.

And that's all he ever wanted to do.

"I'll put it to you this way: When he was little, and he was doing bad in school, I'd have to threaten him -- that he's not going to fight," recalled Flores Sr. "And he would cry and cry, and he would straighten up.

"So I didn't have to whip his ass. He loved boxing -- he always loved boxing. I think that's why he's so special, because he really loves the sport."

For Flores Sr., boxing was also a way of bonding with his son. Beyond training with his father, Flores Jr. recalls countless times when they watched fights together at their home. One particular night and one particular bout stands out to the younger Flores, even though his father wasn't with him that night: the classic encounter between Felix Trinidad and Fernando Vargas in December 2000, with Trinidad stopping Vargas in the 12th round.

"It was crazy how much Fernando was just getting knocked down, but he kept getting up," Flores Jr. said. "He had a lot of heart and he just kept on going. And just the little tactics. Felix was just hitting him real low and he was just doing what he had to do to win. It was just a crazy fight overall. It showed a lot of what boxing is all about."

Flores says his father actually attended this fight at the Mandalay Bay in Las Vegas, and has rewatched it numerous times. While he admires both Trinidad and Vargas, there was one other fighter who stood out above the rest -- Roy Jones Jr.

"I couldn't really watch a full 12-round fight, but when Roy was on, I could watch all 12 rounds,'' the younger Flores recalled. "He was very entertaining. I loved how he was very fluid, he was very comfortable, and he made it seem like he was just having fun in the ring."

Jones, for all his transcendent skills, did not have a textbook style -- an approach better admired than emulated. Still, in looking at Flores' style in the ring, you can see how Jones' approach had an effect on Flores

"The potshots that I do, like the leaping left hook that I knocked out [Reis] with, that's part of what Roy used to do. I started doing that as a kid, and my father taught me how to do it the right way," Flores said.

Overall, Flores' approach to boxing is far more polished. Before he graduated from Cesar Chavez High School in 2018, Flores captured numerous titles, including the 2014 Silver Gloves and the 2015 and 2016 U.S. Junior National Championships.

He was certainly a strong contender to represent America in the 2020 Summer Olympics as well, but the decision was made in November 2016 for Flores to sign a promotional deal with Top Rank at the age of 16, which made him the youngest boxer to ever be signed by the company.

It was a decision that was contemplated for a few months. Several key factors swayed Flores and his team toward the pro ranks. In the past, the boxing tournament was one of the featured events of the Olympics, but now it's relegated to streams and the secondary channels, for the most part. Just as important, as the headgear was taken off for Olympic-style boxing, the decision was made easier.

"I've seen guys at the [Olympic] trials get cut. I mean, I've seen bad stuff," Flores Sr. explained. "So I'm looking at this and saying, 'Is it really worth it?'''

Flores had to wait until after his 17th birthday on May 1, 2017, to make his pro debut. His first eight bouts were in Nevada and Texas, as California's minimum age to box is 18.

But it was clear that at the age of 19, Flores was still growing and building up more natural muscle mass.

"Absolutely, 100 percent," said the fighter's father, who trains him daily at his gym, the Los Gallos Boxing Academy in Stockton. "I see him getting stronger every fight. It's something that's always improving -- he's getting stronger fight by fight and that's something that [Top Rank matchmaker] Brad Goodman looks at, that's how we move him."

It's clear that Flores' journey is just beginning, and with his father at his side, he hopes to continue to build upon his legacy.

"Don't get me wrong, it was a great night [in Stockton back in May] -- an epic night for our city. It was a great night for our family, but that's over now," Flores Sr. said.

"I've got a long ways to go to reach my accomplishments and all that," Flores Jr. said. "So my father and I have got a lot to work on. I have a lot of love for the sport and we have a great understanding of each other."