The seismographs are shaking. 

The anticipation is growing. 

That’s because a rumble is coming.

For the past year and a half, the supervolcano that once was the super flyweight division has been quiet. Not quite dormant, but nowhere near as active or explosive as it had been in recent years.

If that’s going to change — and for the sake of the fighters and the fans, hopefully it does — then that begins with this Saturday’s fight between Juan Francisco Estrada and Jesse “Bam” Rodriguez.

Their contest is the main event at the Footprint Center, a basketball arena in Phoenix, Arizona, and it will air on DAZN. This is a deserving spotlight for a collision between a pound-for-pound stalwart and a rising talent on the verge of stardom.

It is cause enough for celebration whenever two of the best face each other. Perhaps this fight will also serve as the spark that reignites the 115-pound division, which is also known as junior bantamweight. 

Looking at this summer’s schedule, Estrada vs. Rodriguez and the other super flyweight fights in the weeks to follow could be the start of something special, returning the 115-pound weight class to the days when one of the deepest divisions in boxing was also one of the most compelling.

These were the names back then: Carlos Cuadras. Juan Francisco Estrada. Roman “Chocolatito” Gonzalez. Srisaket Sor Rungvisai. They were called the new “Four Kings” of boxing, harkening back to the era when some combination of Roberto Duran, Marvelous Marvin Hagler, Thomas Hearns and Sugar Ray Leonard met a total of nine times over the course of a decade.

Cuadras, Estrada, Gonzalez and Sor Rungvisai met a total of 11 times, beginning with the first fight between Chocolatito and Estrada down at junior flyweight in 2012, and concluding about a decade later with their rubber match at super flyweight at the end of 2022.

There were others who weren’t part of this royal quartet but who nevertheless deserved attention and acclaim.

Naoya Inoue had a three-year world title run from the end of 2014 through 2017. Sadly, the timing didn’t align right for fights with the rest. Chocolatito joined the division at the tail end of 2016 with a win over Cuadras and had his two fights with Sor Rungvisai in 2017, losing one controversially and the other brutally. Estrada arrived at 115 himself at the start of 2017 and took on Cuadras later that year. By 2018, Inoue had moved up to bantamweight to begin his great run there.

Kazuto Ioka and Donnie Nietes entered the super flyweight ranks in 2018 after successful runs in the lower weight classes. Ioka and Nietes fought twice, Nietes winning the first by split decision in 2018 and Ioka avenging that with a unanimous decision win in 2022. Their paths otherwise never converged with the Four Kings. Nietes hasn’t fought in two years, is now 42 years old and teased a comeback earlier this year. Ioka is not only still around, but he remains relevant and continues to defend his title, including a unanimous decision win about a year ago against Joshua Franco, a former titleholder who happens to be Rodriguez’s older brother. 

Let’s pause on that for a moment — we’ll return to Ioka in just a couple of sentences.

That’s because this Saturday’s fight between Estrada and Rodriguez is the start of a beautiful three-week period. Over the span of 21 days, all four world titles are on the line at super flyweight.

Estrada vs. Rodriguez is for the WBC belt and Estrada’s lineal championship, earned with his 2019 win over Sor Rungvisai. On July 7, Ioka (WBA) will face fellow titleholder Fernando Daniel Martinez (IBF) in a unification bout. And on July 20, Kosei Tanaka will defend his WBO belt against Jonathan Rodriguez, who fell short in his previous title challenge, against Jerwin Ancajas, back in 2021.

Oh, and Chocolatito is returning July 12, fighting for the first time since that third Estrada match. He’ll headline in his hometown of Managua, Nicaragua, against a former junior flyweight and flyweight contender named Rober Barrera. 

Gonzalez vs. Barrera is up at bantamweight. If Chocolatito wins, he could remain at 118 and face any of the four titleholders there. All four are from Japan, a country that has been like a second home to Chocolatito; he’s fought there 10 times over the course of his career. However, if Chocolatito is willing and able, he could also remain in the mix at 115, or any of these super flyweights might also be willing to move up three pounds to take on the living legend.

The second tier of the super flyweight division includes Pedro Guevara, a former 108-pound titleholder who just beat Andrew Moloney by split decision last month. David Jimenez, a former flyweight contender, scored a big win over fellow contender John “Scrappy” Ramirez in April on the undercard of Devin Haney vs. Ryan Garcia. Cuadras remains in the picture, given his November split decision victory over Guevara. Sor Rungvisai has fought a series of no-hopers since getting stopped two years ago.

The person who did that to Sor Rungvisai? Bam Rodriguez.

That was part of the run that established Rodriguez, when he went from prospect straight into the spotlight, seizing an unexpected opportunity. In February 2022, Cuadras and Sor Rungvisai were supposed to fight in a rematch of their 2014 bout. Sor Rungvisai fell ill, however. Rodriguez was scheduled to appear on the undercard in a 108-pound match. Instead, he moved up two weight classes to fight for the vacant WBC title, putting forth an impressive performance and taking a unanimous decision over Cuadras.

It was reminiscent of when Terence Crawford stepped in as a late replacement opponent himself, dominating Breidis Prescott in March 2013 and reaping the rewards. For Rodriguez, the win over Cuadras led to an eighth-round technical knockout of Sor Rungvisai in June 2022. 

Less than three months later, Rodriguez had a tougher time in his unanimous decision win over Israel Gonzalez — who had come up short in his three past title fights against Ancajas, Khalid Yafai and Chocolatito — but who remained (and still remains) a viable contender at 115. 

The final month of 2022 brought Estrada-Chocolatito 3, which Estrada won by majority decision. Although Rodriguez had deposed two of the Four Kings in Cuadras and Sor Rungvisai, there would be no fight with the remaining two in 2023. 

Instead, Rodriguez moved down to flyweight and won a vacant world title, though he struggled with Cristian Gonzalez’s movement and also had to fight through a broken jaw. After healing, Rodriguez returned last December with another impressive win, taking out fellow titleholder Sunny Edwards in nine rounds to unify two belts.

Now Rodriguez is back at 115. Estrada is the perfect choice of opponent. For us, of course, but also for both of them.

“He’s a legend of the sport. He’s been around for many years. He’s been around since I was an amateur. He was a champion when I was still an amateur. So to share the ring, it’s an honor, but come June 29, I’m going to take over,” Rodriguez said recently. “I believe a win over Estrada will make me the face of the lower weight divisions. From what I've already accomplished, I’m like one fight away. This fight would seal the deal.”

Estrada has the advantages of experience, both in terms of time in the sport — he’s been a pro for 16 years while Rodriguez has been in the paid ranks for seven — and the level of opposition faced. But there’s also the combination of wear and tear from time, training and tough fights, plus the potential consequences of the long layoff. Will that rest lead to rust? Or will it turn out to be more helpful than harmful?

“Everybody is saying that I’m about to retire. But I actually consider that, at my 34 years of age, I have about four years left in my career,” Estrada said. “So the truth is that I think a lot of people are wrong.” 

As for the time away:

“It’s been a year and a half since my last fight, but I haven't been out of the gym. I’ve actually been training,” he said. “Although I have not fought in this period, it’s been good for me because […] I like to be with my family, I like to be with my children. So I don’t think I’ve been wasting time.”

Rodriguez, meanwhile, is younger and fresher at 24 years old. His body hasn’t been put through as much. Then again, he had those tougher outings against Israel Gonzalez and Cristian Gonzalez. That’s something Estada felt worth mentioning.

 “He’s been a super flyweight champion before, but he didn’t look very good and had to move down to flyweight, and I’m a fighter who made my debut at bantamweight and I’ve been moving down. I’m more used to these divisions than he is. And maybe he will feel [the punches] a little bit more. I consider myself to be a very complete boxer. I can go out. I can pressure. I can brawl. I don’t think Bam is going to have it easy.”

Estrada indeed started off moving up and down between flyweight and bantamweight before going to 108 to face Chocolatito. And he’s indeed been at 115 much longer. But just because Rodriguez was lighter doesn’t mean he should be taken lightly. Estrada does acknowledge Rodriguez’s quality — “Bam Rodriguez will be a test for me” — but he also inserted caveats in Rodriguez’s performances, be they Estrada’s legitimate beliefs or a form of mind games:

“Bam has been a good fighter,” he said at one point. “But a lot has to do with how his rivals have performed. Maybe they were not doing well and that’s why he looks extraordinary.”

“I was there at [Rodriguez’s fight with Edwards] and he looked great, spectacular,” he said at another point. “He knocked out Edwards very good. But then again, Edwards is a flyweight. It’s a different story in super flyweight.”

Rodriguez, meanwhile, counters that the verdict is already in about how good he is, and that this match with Estrada will remove any lingering question marks. (His team also did something wise: setting up sparring with Chocolatito to give Rodriguez more high-level experience and perhaps an extra boost of confidence.)

“I just proved to everybody that I’m the real deal,” Rodriguez said, referring to his wins in 2022 and 2023. “People still to this day doubt me. They say that I’ve been in with washed-up fighters. But this is a fight where I can prove that I’m the real deal.”

And then, pending a contractual rematch clause being exercised, the winner can keep moving forward. 

“I’ve been writing my legacy,” Estrada said. “And I want to keep making history.”

“I don’t want to be fighting for a long time, so I want to get big fights and give entertaining fights to the fans, just be pure entertainment,” Rodriguez said. “Seeing all the fighters that have become undisputed in the last few years, holding all the belts in the ring, it’s very motivating to me. To be undisputed at 115 pounds would be a great accomplishment.”

The reality of this fight is already plenty exciting. Thoughts of the bouts that could follow make this match even more enticing.

It’s no wonder, then, that the seismographs are shaking, that the anticipation is growing. 

A rumble is coming — and aftershocks are sure to follow.

Follow David Greisman on Twitter @FightingWords2. His book, “Fighting Words: The Heart and Heartbreak of Boxing,” is available on Amazon.