April 3, 2005. It’s 02:00 in Washington.

Stephan Weiler is woken by a “dreaded call”. A voice said: “Is Becky Zerlentes your wife?’

“I said ‘yes’, and the official from Denver Health Medical Center and Hospital told me I need to get to the airport as quickly as possible. Her condition was deteriorating.”

Up until that day, a female boxer in the United States had never died in a sanctioned fight.

In succumbing to that devastating blow, Zerlentes – who three years previously won a regional boxing title – had rewritten history.

While the tales of fighters like Johnny Owen and Jimmy Doyle, external are enshrined in history, the impact of Zerlentes’ death on the community in Denver and on those who loved her has remained private.

Zerlentes’ love affair with combat sports defined her life, an overwhelming rush every time she stepped inside the confines of a boxing ring or MMA cage.

Like most amateur fighters, 34-year-old Zerlentes embraced a career away from the ropes, working as a geography and economics instructor at Front Range Community College’s Larimer County campus, earning a master’s and PhD.

The buzz she enjoyed inside the classroom was complemented by her love of sport, especially in combat.

On that fight night, Weiler continued his three-year stay at the Federal Reserve, the country’s central banking system.

He had constantly been asked by Zerlentes to return to Fort Collins, the former military outpost nestled in the foothills of the Rocky Mountains, and promised he soon would.

Facing Heather Schmitz, Zerlentes was taking part in the Colorado State Boxing Senior Female Championships at the Denver Coliseum in Colorado, a venue that has crammed more than 10,000 people in when the Rolling Stones or Rage Against the Machine have been in town. Both women wore protective headgear.

For two rounds Zerlentes worked, trading punches with Schmitz until the third.

With a blow to the head, just above her left eye, Zerlentes staggered forward, struck the canvas and fell unconscious – a state she would remain in until her death the following morning.

“The doctor in the ring said her pupils were fixed and dilated when he saw her first and already there was a chance that brain damage had occurred,” Weiler, now a professor, said.

By 06:30 Weiler was on a flight to Denver and immediately made his way to the hospital. There he saw Zerlentes.

“The amount of damage to Becky’s brain was remarkable given that it was a fairly glancing blow,” he said.

“It was not a hard hit… but the brain had become bruised to such an extent that it could no longer operate.”

The life support Zerlentes had been placed on was beginning to fail, and that “clinically she was probably already dead in the ring”, Weiler recalled.

And then he had to make a choice.

“At about noon that morning, the decision was made, knowing that her condition was deteriorating, I made the choice that it was time, as I knew the window for organ donation, which Becky so fervently supported, was closing,” he said.

The reaction to her death was immediate.

Tributes flooded in across Denver. Colleagues, students and others who knew Zerlentes described the warmth and tenacity of one of the college and community’s pillars.