ST. LOUIS -- Roman Bürki just wanted to find a home.

It was the spring of 2022 and after 13 years in the professional game, the former Switzerland No. 1 knew his time with Borussia Dortmund was ending. The grind of the pro game -- a goalkeeper is considered to be only as good as their last save -- had worn him down. Enjoyment was in short supply.

"I just was looking for fun again," Bürki told ESPN. "And I think how the soccer is looked at in Europe, it's more or less everywhere the same. It always comes with a lot of pressure. If you deliver, you're good. If you don't deliver, you are the target [for criticism]. It was difficult for me in Dortmund the last years."

So in March of last year, Bürki packed up his things and headed to St. Louis City SC. Fun, and a sense of belonging, is precisely what he has found.

The MLS expansion team has surprised nearly everyone in 2023, claiming the top spot in the Western Conference, guaranteeing homefield advantage at least through the MLS Cup playoffs conference finals. Bürki has been at the heart of St. Louis's success.

He leads the league in goals prevented -- a measure of expected goals (xG) on target minus goals conceded -- with 11.49 and is fifth in save percentage at 74.5. Given that St. Louis is tied for fourth in MLS for the most shots on goal allowed, with 174, Bürki's saves have been critical, putting him among the favorites for Goalkeeper of the Year.

"He gives us a lot of lifelines," said St. Louis center-back Tim Parker.

St. Louis sporting director Lutz Pfannenstiel goes so far as to say Bürki isn't just the best goalkeeper in MLS this year, but in the history of the league. That kind of support and assurance has made St. Louis a perfect fit for Bürki, so much so that he is enjoying the game again.

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"To come here and just feel the whole support from the fans, from the whole club, from the city, feels extremely good," Bürki said. "And I think that I just needed that."

Like playing with 13 men

Bürki was one of the first players Pfannenstiel targeted when he began assembling his roster. It's an approach that raised eyebrows: in MLS, solid keepers can be had for relatively modest hits to the salary budget. Pfannenstiel, a goalkeeper himself during his playing days, didn't just want solid; he wanted exceptional, the better to establish the spine of the team.

"I always have that saying, if you have a modern goalkeeper, you play with 13 men," Pfannenstiel said to ESPN at St. Louis City's training facility. "You have the last defender and the first attacker, so you play with 13. ... He is very good in opening the game, but he's also very good in reading the game defensively, when to come, when not to come. ... I think he just has a very complete game as a keeper."

Players from overseas are constantly being linked to MLS, but getting them to sign on the dotted line is another matter. Pfannenstiel thought he had his sales pitch perfected. With Dortmund's blessing, he planned to bring Bürki to St. Louis for a few days in March of 2022, show him around town, give him a glimpse of the training facility and stadium that were under construction, and sell him on the project. He made one mistake: he tried to sell Bürki on the climate, forgetting that in March, the weather gods of the Midwest can be beyond fickle.

Sure enough, the weather turned sour.

"I was expecting it would be spring-y and nice," Pfannenstiel said. "It was gray, snowy, icy roads. It was the most miserable look I've actually witnessed in St. Louis when he was here, which is terrible. And I was like, 'Oh f---,' telling him, 'Hey, it's great weather here. It's always sunny, beautiful summer coming here.' And he saw you are actually in the middle of Siberia. That was the tough one."

Fortunately for Pfannenstiel, the St. Louis project proved to be an easy sell. Bürki said he had opportunities in Europe, but was looking for something special.

"It's hard to make history in America," Bürki said. "So it was also an opportunity for me to come here and be one of the first signings in this new club. I was here and I saw the stadium was nothing. There was only construction and sand on the floor and nothing was built, really. And now to see this whole thing growing and now finally be here, it just feels good."

'I always knew about my qualities'

Bürki rose through the youth ranks first at local club FC Münsingen and then Young Boys, eventually making his way to Grasshoppers in Zurich, Bundesliga side SC Freiburg, and then Dortmund. His first five seasons with Die Schwarzgelben were successful, yielding a German Cup triumph in 2017.

Bürki even formed a connection with one Christian Pulisic, sharing moments both happy and terrifying. In April of 2017, it was the latter.

Bürki and Pulisic were sitting next to each other in the back of the Dortmund team bus on the way to the first leg of their UEFA Champions League quarterfinal with AS Monaco when three bombs were detonated as the bus passed. There was shock at the first bomb, and then the second. Bürki noticed that a window was broken, and teammate Marc Bartra was bleeding from shrapnel lodged in his arm.

"I remember Christian was like frozen," Burki said. "I was really pulling him down on the floor. I was laying basically on him a little bit because we were just really scared. And it was really like something that I've never felt before, fear and adrenaline. You don't know what's going to happen, if people are coming, or whatever. And then we were just waiting in the bus until somebody said, 'It's safe. You can come out.'"

Even today, Pulisic is grateful for his teammate's intervention, and his friendship.

"We've had some really good bonding moments over the years," Pulisic told ESPN of his time with Bürki. "He's a top guy. He always trained really hard, and I thought he was a great keeper. He always handled himself very well. He is a top professional, so for me, I'm happy to see him succeeding now."

While the trauma of that night eventually faded, the subsequent years in Dortmund proved difficult. Bürki lost his spot in the lineup during the 2020-21 season, and he soon realized that people's attitudes toward him could be as fickle as the weather.

Earlier that year, Dortmund had signed Bürki to a new contract, saying he was the goalkeeper of the future. The whole club was behind him, asking him how he was doing. "You kind of live for that," Burki said.

And after he was benched? "That gave me the feeling that you are only important when you deliver," he said. "If you are not, it's kind of like, 'You're here, you're getting paid, but we kind of want you to go somewhere else so we don't have to pay you anymore.'"

That is until a week before the 2021 German Cup final against RB Leipzig. Starting keeper Marwin Hitz was injured, thrusting Bürki back into the lineup. Then, all of a sudden, his phone started ringing again, the club hierarchy asking how he was feeling.

"This is weird," Bürki recalled thinking. "You just want to make me feel good now because I have to play the final, because you're scared that I'm going to mess up, because I have no confidence. But I never lost confidence. I always knew what I can do. I always knew about my qualities."

Dortmund prevailed over Leipzig 4-1 thanks to two goals each from Jadon Sancho and Erling Haaland. Even as Bürki raised the cup, the feeling was bittersweet.

"I couldn't really enjoy the moment because I knew I'm going to leave at some point because it's not going to change," he said. "The decision is made. So I knew that I'm going to play this final for me, for myself, to show the people who are watching what I can do and maybe to get an offer somewhere."

'We can aim to be a great team'

While he got the offer from St. Louis that he'd been looking for, Bürki did experience some culture shock upon his arrival.

For a start, he wasn't playing MLS games during the 2022 campaign, but in MLS Next Pro, the de facto reserve league. This was part of Pfannenstiel's grand plan to get players like Bürki, João Klauss, Eduard Löwen and Tomas Ostrak into the team and get them acclimatized not only to each other, but to the city. That way, when the players reported for 2023 preseason, "They were coming home," as Pfannenstiel put it.

It was certainly different from what Bürki was accustomed to. Certainly the level of play was a few steps below where he had come from, and off the field, instead of flying charter like they would in Europe -- and eventually when St. Louis began MLS play -- the team experienced all the headaches of flying commercial.

St. Louis has since provided that long-sought level of comfort, and soon after he arrived, Bürki found himself being appreciated again. So much so that he was voted captain by his teammates prior to the 2023 season.

That brings him to the part of his move that he says has been the most difficult.

Bürki is fluent in English, but finding the right words during his pregame speech can still be difficult. "I try to motivate [my teammates], but sometimes I just look at their faces and [I'm] like, 'I'm sorry. I try my best,'" he said.

Bürki still manages to get his point across. The words may not come easily, but actions and examples can pick up the slack. "Sometimes it's kind of funny, I have to be honest," Parker said of Bürki's pregame speeches. "But he emphasizes what we want to be about. It's about the hard work, playing for each other, and I think that's one of the biggest things that his emphasis has been on this year is play for the guy next to you."

Now the playoffs beckon.

By just about any objective measure, St. Louis has had a successful season. The low expectations usually reserved for expansion teams have been vastly exceeded. As such, St. Louis locked up its spot in the postseason weeks ago, but even in September, Bürki sensed that the team was taking its foot off the gas a bit. Sure enough, St. Louis ended the campaign with two defeats.

His experience tells him that opportunities to do something special only come around every so often. In a league like MLS that is built on parity, that is even truer. That is the message Bürki is driving home now.

"We can now decide to be a good team, go into the playoffs, survive maybe one round, then go back home and call it a good season. Or we can aim to be a great team and stay in it, work hard and not be happy just with achieving the playoffs," he said. "I mean, maybe next season we're not going to the playoffs, so let's try to make this season that we have, what we work for already, to reward ourselves and go as far as possible."

What is certain is that Bürki is dug in. His intentions are to live in the present. A possible return to Europe is something he says he hasn't thought of.

"If you think too much about the future, you're going to overthink things and like, 'Oh, what I need is to have something for the future,'" he said. "Of course you need to have a plan, but you never know how it's going to turn out. Something could happen. So I am really happy to be here. So I just play as long as my body is ready to play and to perform every day and as long as I have fun."

St. Louis City is hoping the fun lasts all the way to MLS Cup.