ZEELAND — When the ball got into Mack Kooman's hands, he knew he was in for a fight.

The Zeeland East running back burst through the line, carried two Holland defenders with him and dove across the goal line for a five-yard score. When the dust settled in the end zone, a wall of emotion overcame him and he broke down and started to sob.

On the surface, Koopman's reaction to hitting paydirt didn't make a ton of sense. It was a score in the waning moments of a 68-44 Zeeland East win over the Dutch last season. The touchdown had literally no impact on the result of the game — but in the grand scheme of things, that play meant everything.

When the Chix took a knee after the game, the then-junior stood in front of his team and told them about the bigger journey it took to get into the end zone that night. It was one virtually nobody in Zeeland knew about.

"We were ecstatic for him after we learned his story, just watching a guy who works his butt off every day and now we know has been through so much, it was emotional for all of us," said senior linebacker Nick Williams. "We still talk about that moment a lot today even outside of football."

That night marked Koopman's first touchdown since his freshman year at Langely High School in Virginia. He was making a bit of a name for himself out East, getting pulled up to the varsity roster toward the end of his first high school season. Just a few months after the season had ended, he was starting to train for a sophomore campaign where he was primed to make a big impact for his squad.

As he started getting back into shape right after Christmas, he realized something wasn't quite right. He was always overly exhausted and had a bit of a fever. The symptoms got worse and his family eventually took him to the hospital with what they thought was an extreme case of mono.

Doctors ruled out mono pretty early on after they started running some tests on the 15-year-old. Still, they couldn't figure out what, exactly, was wrong. All they knew? It wasn't good, and it was very serious.

"I was just slowly dying, like my organs were literally dying," Koopman said. "Everything that should be working was failing and my body was just finishing itself."

The first diagnosis at the hospital was secondary hemophagocytic lymphohistiocytosis, more commonly known as HLH. The blood cells in Koopman's immune system were working too hard. When an infection pops up, those cells are meant to destroy the damaged cells in the body to get the person healthy again.

Secondary HLH is dangerous but treatable. Doctors loaded Koopman up with steroids and tried to hunt down the underlying issues causing his HLH. The drugs caused him to gain more weight than he ever had before. He still wears the stretchmarks on his body like battle scars. After some time, though, they realized Koopman didn't have any damaged cells to attack. His immune system just kept destroying all his healthy cells.

It wasn't secondary HLH — it was primary HLH.

The difference between the two aren't that major from a physical standpoint. The disease is still doing the same thing to the body either way. The separation between the two comes in the treatment. Once doctors track down secondary, they can treat it — but primary HLH is genetic, and there are very few ways to tackle it.

If left untreated, most people die from the disease within six months.

There were two options on the table for the teenager: Do nothing and have his body waste away, or undergo chemotherapy to kill off the overactive cells, then get a bone marrow transplant to regenerate new cells, replacing those killed by the chemo. Koopman had been battling his whole life on the field, so it was only natural he took that same mentality in the hospital room.

"I've always been a fighter, I've never been the kind of guy to give up easily on anything," Koopman said. "In football, I mean, my coaches aren't going to let me give up, so I had that same mindset and I knew I was going to make it through."

His body accepted the transplant and responded well to the chemo drugs, for the most part — but there was still a long road to go.

Koopman had several debilitating side effects from the procedure. His vision was gone entirely for months, and he was forced to use a feeding tube to get enough calories to stay strong enough during his recovery. If that weren't enough, it was June 2020, and the world was still grappling to understand the new COVID-19 virus. Pandemic protocols severely limited the number of people who were allowed to visit him in the hospital.

"That process was really hard. I went blind for basically a couple months, I was really depressed for a little bit," Koopman said. "I was just sitting in my room, by myself in the quiet and kept my lights off, I couldn't see anything and I just felt alone."

His vision eventually came back, though he still has issues with it from time to time. He took a laundry list of different medications throughout recovery, but the only real medicine for his depression was football.

He got back to the field as fast as he could, even when he probably wasn't physically ready for it. In the wake of the pandemic, the state of Virginia played a spring season in 2021 instead of the normal fall campaign, starting just about a year after Koopman's diagnosis. 

His first practice ended with a trip back to the prison that confined him for much of the last year — the hospital. 

"I go out onto the field, I go out and try to make a cut and I just snap my ankle," Koopman said. "My legs were like chicken legs at that point, I was straight bones and skin, it was terrible, I had zero muscle on me."

The break put him in a cast for what doctors thought would be six weeks. The recovery would force him to miss the majority of the condensed season, if not all of it. That wasn't good enough for Koopman. He followed every instruction the doctors gave him and was out of the cast in two weeks, all the while doing upper body workouts to get his body back in playing shape.

Once he was out of the cast, the chance to play the game he loved was the only thing on Koopman's mind. He strapped up an ankle brace, made it as tight as he could, and laced up his cleats just four weeks after the break.

He saw action in the final game of the year. Nothing major, serving as a wing on field goal coverage — but being back on that 120-yard patch of grass was all he needed. It made him feel like he was home again after over a year away. That sort of desire to get the job done by any means necessary is inspiring to the players around him today.

"Him going through what he did, that's a big deal, and as soon as we learned about it we all supported in any way we could," said Zeeland East junior quarterback Austin Keur. "It proves to us that, if he can beat those things and get back on the football field, then we should go out and do whatever we can, play our best game, regardless of the circumstances."

His family moved to Michigan last summer. In the fall he saw the field a solid amount for Zeeland East, but by no means was he a featured part of the Chix offense. That has a good chance of changing this year, and it also seems like he'll be a starting defensive back on the other side of the ball. Though what he does on the field doesn't matter all that much to those around him.

Joe Woodruff, Zeeland East's second-year head coach, knows that players with Koopman's fortitude and mental toughness don't come around often. Each day as the senior gets healthier and more comfortable back in pads, he shows more and more glimpses of what he can do when he's not fighting a deadly disease.

"He has all the character in the world that a coach could want, we're working on the football side since he's been away so long, but he's getting better every day," Woodruff said. "He's done everything we've asked him to do on the football field, but I know he's not a guy that high school football will be a high point of his life, he's going to be successful in anything he chooses to do."

Koopman sacked HLH, tackled a nasty broken ankle and finally felt whole again when he scored that touchdown against Holland last fall. The only thing left for him to do now is show the rest of the world what he already knows he's capable of.

"I'm very excited to finally show out, I think I had a big future ahead of me freshman year that kind of got ruined by everything that happened," Koopman said. "So it's really good to finally be back to normal and start playing full-go again."

— Contact Assistant Sports Editor Will Kennedy at will.kennedy@hollandsentinel.com. Follow him on Twitter @ByWillKennedy and Facebook @Holland Sentinel Sports.