When Seattle Kraken goalie Philipp Grubauer was preparing for his first physical with the new franchise, there was one step he could skip.

While everyone else on the team was taking their vision tests, he finished early. The German goaltender has color vision deficiency, more commonly known as colorblindness, and he’s known that since he was a child.

Joining the Kraken — the third team of his NHL career — carried a lot of newness for Grubauer: finding an apartment, taking on the duties of a No. 1 goalie, and explaining to a new set of teammates that he doesn’t see the same way they do. “It’s kind of like when you wash jeans too much and then they look a little bit worn out,” Grubauer said. “[Color] doesn’t pop to me the same way.”

Grubauer is one of a handful of players in the NHL known to have color vision deficiency. The league doesn’t keep track of the number, but FiveThirtyEight talked to four players for this story. Each of them has the same condition, classified as red-green colorblindness, the most common type. 

One in 12 men, or 8 percent of the world’s population, is colorblind, according to the U.K. nonprofit group Colour Blind Awareness, but only 1 in 200 women, or 0.5 percent of the population, has the condition. In all, about 4.5 percent of the population has some form of color vision deficiency.

The NHL players we interviewed were born with color vision deficiency, which in males is inherited from the mother. Sometimes, though, colorblindness can result from age, chronic illness or accidents. 

During one of Grubauer’s first practices with the Colorado Avalanche in 2018, the goalie said out loud that he couldn’t see “anything out there.” Teammate Tyson Jost was intrigued.

“His line was wearing, like, gray, and I was like, ‘I can’t see it,’” said Grubauer, who signed with the Kraken in the offseason after three seasons with the Avalanche. “So he was like, ‘What do you mean you can’t see anything?’ I said, ‘I don’t know if I’m passing it to a black jersey or burgundy,’ so he was like, ‘Wait, are you colorblind?’ I was like, ‘Yeah, you too?’”

For people with red-green colorblindness, blues and yellows stand out, but greens are dull. They often confuse shades of blue with shades of purple and have trouble identifying pale shades of most colors.

People with dichromatic color vision have only two types of cones in the retina that perceive color — compared with the usual three, which detect red, green and blue light — and can’t see some colors because they lack the receptors to see light in those colors. Red and green cones largely overlap, so when one is gone, usually the other is, too.

Philadelphia Flyers goalie Carter Hart is also red-green colorblind. He said he can confuse shades of brown, yellow, orange, red and green. It doesn’t affect his plays that much, but it does affect how he experiences life outside of hockey. He hadn’t truly seen his dog until the first time he tried color-corrective glasses.

“My dog is part beagle and part Jack Russell terrier,” he said. “He’s brown and white, a little bit of black, and his colors just looked so bright and vivid. I always thought he was dull-color-looking. So that was pretty cool, but after 10 minutes my head started to hurt. I felt bad my parents spent money on those glasses. I was like, ‘I’m not going to wear these,’ so I gave them back.”

Hart said he has an idea of what the Flyers jersey looks like — “I think ours is a burnt orange” — but some darker uniforms can be tougher for players on teams that don’t have unique colors.

When Jost, who was recently traded to the Minnesota Wild, joins a new team, he needs to explain his color vision deficiency so he can practice and participate without difficulty.

“I told the trainers to put me in white every time so I can tell what line I’m on,” Jost said. “But you know your linemates and stuff, so it’s not that big of a deal. … I know we’re burgundy, but I don’t really know what that looks like, I guess.”

In the NHL, where opposing teams face each other in alternating dark and white jerseys, colorblindness doesn’t typically get in the way because light and dark are usually easy to differentiate for people with color vision deficiency. Everything looks a tad different than it does for people who don’t have color vision deficiency, but the ice is still white and the puck is still black.

Youth hockey, however, is different. Jerseys aren’t always the same dark-on-light contrast.

“In a few minor hockey tournaments or Hockey Canada events,” Jost said, “we had to switch jerseys because I didn’t know who was on the team.”

Unlike in the NFL, where Color Rush jerseys once caused nightmares for colorblind athletes and fans, the NHL — and NCAA — hasn’t strayed from dark against light for its uniforms.

But it’s day-to-day life that gets more interesting for colorblind NHL players.

Jost said he realized he was genuinely affected by color vision deficiency in the third grade, when he did an art project of the sky that he thought was “absolutely unbelievable” but his teacher failed him.

Jost’s mom wasn’t happy. “She went in and was like, ‘The kid’s colorblind, cut him some slack here,'” he said. “My grandpa had it, too, so it wasn’t surprising to anyone in my family.”

Justin Schultz, a defenseman for the Washington Capitals, also said he has to explain his colorblindness off the ice more than on.

“[My wife] will have to match my ties to my suits,” said Schultz, whose brother is also colorblind. “Sometimes I’m not sure what that looks like, so that can be, like, a little tough, like I can know kind of what it is close to looking like.”

Colorblind hockey players enjoy a bit of camaraderie when they find this rare similarity with an opponent or teammate. But for the most part, their world is still colorful — just not in the same way.

“Anyone who ever finds out is always asking me, like, ‘What color is that?'” Schultz said. “And I’m like, ‘Well, that’s blue.’ That’s my blue. That’s how I know what blue is, because that’s my blue.”

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