The life of a goalkeeper is akin to that of a high-wire performer. A keeper’s mistakes are usually remembered with greater clarity than their successes. Errors oftentimes end up reflected on the scoreboard after all.

And yet the only way for a young goalkeeper to minimize those errors is to accumulate enough game experience so that plays become automatic, the odds of making a save or sniffing out danger are maximized. Acquiring that experience often means being thrown into the proverbial deep end. The mistakes are tolerated as long as there is an upward trajectory.

That is the challenge facing Chelsea and United States goalkeeper Gaga Slonina.

Slonina, 20, is headed out on loan to League One side Barnsley for the duration of the upcoming season, and he hopes to take the next step in his soccer education.

“It’s going to be a great experience for me in League One, to feel a bit of English football,” he said via text message. “I think it’s a great stepping stone for me and my career. It’s definitely going to be an experience playing 40+ games in a season.”

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This marks the second consecutive season that Slonina will be loaned out, having played 34 matches during the last campaign for Belgian side K.A.S. Eupen.

Slonina called the 2023-24 campaign “a one-of-a-kind experience”, even as it was chock-full of tough lessons. It certainly wasn’t difficult to find negatives. Eupen was relegated from Belgium’s top flight. Slonina’s individual numbers were sobering as well. According to Fbref.com, in 28 league appearances, his goals prevented per 90 minutes, was -0.06, tied for the second-worst mark in the Belgian Pro League for keepers who logged 900 minutes or more. In other words, Slonina wasn’t making the saves he was supposed to make as often as other keepers in the league.

But numbers don’t always tell the whole story. Slonina was under immense pressure throughout the season, facing 159 shots on target, the second-highest number in the league. The fact that Eupen struggled throughout the campaign meant that Slonina was often left exposed.

“I’ll be honest with you, we didn’t help him enough, you know?” said then-Eupen defender Victor Pálsson, who is now with Plymouth Argyle in the Championship. “Us defenders, we let him down a number of times. I mean, Gaga made his mistakes. We all make our mistakes, but we didn’t support him the way we should have on the field.”

He added, “He was playing in the worst team in the Belgium league. I would say, with the circumstances that he was in, he did really well.”

The positive is that Slonina logged 3,060 minutes of playing time in all competitions. This might be the most critical stat of all. Goalkeepers are forged by their experiences. Each shot, each decision is like another layer of armor that is affixed to a keeper’s game. The fact that Slonina got that kind of playing time at age 19 (he turned 20 in May) should see his overall improvement accelerate, even as he’s taken a few lumps.

He certainly showed enough to U.S. under-23 manager Marko Mitrovic to be selected for the U.S. Olympic team, though he was an unused substitute in each of the Americans’ four matches.

“I think the most important thing for me right now is how much game time I’ve been able to get in my first real season in Europe,” Slonina said in an exclusive interview with ESPN. “Because I think just breaking into the European scene, it’s not so easy as a player, and even more so as a goalkeeper.”

This is not to say that the Addison, Ill. native didn’t feel the pain of Eupen’s relegation. The Pandas finished the regular season third from bottom, meaning it was placed in a four-team group stage comprised of the bottom four finishers, with the winner staying up, and the second-place finisher going to a further playoff against a second-tier team. Eupen should have at least survived that stage in second place. It didn’t work out that way, with Eupen going winless in its first five playoff games before securing a 2-0 win over RWD Molenbeek on the final match day when the Pandas’ relegation had already been confirmed.

Slonina called going through a relegation fight as “a special kind of pressure,” one that was ever-present, and near impossible to clear from his head. That’s the case even now that he’s moved on to the next stage of his career.

“It’s disappointing to go and build relationships and bonds with people you consider your brothers and family at that point,” said Slonina. “Being with them for a year, seeing [us] struggle, day in and day out of difficult training sessions and difficult games, where we just couldn’t get a result. I mean, it’s super disappointing. I don’t know if a lot of other players felt this, but [I had] a feeling of regret that we didn’t do enough earlier in the season. So it’s kind of a mix of pretty bad emotions.”

To those who have known Slonina the longest, they expect the keeper’s mentality to push him past the disappointment of relegation. Olympic team boss Mitrovic first encountered Slonina as a 12-year-old, when the keeper and Mitrovic’s son, Matija, were both in the Chicago Fire academy together. From the beginning, Mitrovic noticed something different in Slonina.

“Gaga was always, I would say, like a young, old man,” Mitrovic said with a laugh. “Kids are kids, which is normal. They’re like 12 years old and immature. I think Gaga, he seemed more mature than his generation. And I’m not saying about the way he looks. It’s more of his mentality and approach to the game.”

Adin Brown, who was the Fire’s goalkeeper coach when Slonina joined the Fire first team at age 15, and is now with the San Jose Earthquakes, recalled how on the first day of practice, he told the two veteran goalkeepers they were in to start a scrimmage, leaving Slonina to watch.

“[Slonina] gave me this look, ‘I’m not playing? I’m not going first?” said Brown. “And I think from that moment I was like, ‘Wow, this kid’s got some drive. He’s got some ambition.'”