Leverkusen's goalkeeper Lukas Hradecky talks during an interview with the Associated Press at the BayArena in Leverkusen, Germany, Dec 2, 2019. (MARTIN MEISSNER / AP PHOTO)

LEVERKUSEN, Germany - Any goalkeeper can have a hard time against Bayern Munich. It's harder if you can't see the ball.

Bayer Leverkusen keeper Lukas Hradecky dislodged a contact lens while playing against the German champions on Saturday, but he still helped his team to a surprise win.

The problems started when the Finnish goalkeeper took a shot from Serge Gnabry to the chest midway through the first half, with Leverkusen leading 1-0.

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First of all, I couldn't breathe for 30 seconds. Then I realized that my contact lens was wrapped up in the corner of my eye so for one minute or so I couldn't really see with the one eye

Lukas Hradecky

"First of all, I couldn't breathe for 30 seconds," Hradecky told The Associated Press on Monday. "Then I realized that my contact lens was wrapped up in the corner of my eye so for one minute or so I couldn't really see with the one eye."

A trip to the bench for medical treatment helped - sort of. A team doctor put the lens in backward, leaving Hradecky to survive until halftime with skewed depth perception.

"It's difficult to explain for the guys who don't wear contact lenses. It's there, but if it's the other way around it's very disturbing," he said. "You can still see better than without it, but it's scratching and annoying."

Before Hradecky could get a new lens at the break, Thomas Müller leveled the score for Bayern, but Leon Bailey immediately responded with his second goal to restore Leverkusen's lead. Thankfully for Hradecky, Bayern missed the target with other shots from dangerous positions.

In the second half, Hradecky really came through. Sight restored, he stopped a barrage of Bayern shots and enjoyed some luck as the Bavarian team hit the woodwork repeatedly.

That ended fourth-place Bayern's perfect run - four games, four wins, no goals conceded - under interim coach Hansi Flick. It was a crucial win for Leverkusen, recovering to seventh in the Bundesliga after a patchy start to the season.

Leverkusen is a young, ambitious team and the 30-year-old Hradecky one of its oldest players. After qualifying for the Champions League last season, its players now want to beat top teams.

Getting into the rhythm took a while, with big losses to Borussia Dortmund and Juventus along the way, but a 2-1 victory over Atletico Madrid on Nov. 6 turned things around. Since then, Leverkusen is unbeaten in five games as it prepares to face Schalke on Saturday and Juventus four days later.

Leverkusen goalkeeper Lukas Hradecky, right, saves a shot from Bayern's Robert Lewandowski during their Bundesliga soccer match in Munich, Germany, Nov 31, 2019. (TOBIAS HASE / DPA VIA AP)

"Maybe we respected the opponents too much. We were giving them too much credit," Hradecky said. "And now after beating Atletico we realized, I think, what we need to beat these world class teams."

That recipe is more about self-belief than any tactical shake-up, Hradecky added.

Leverkusen is surrounded by bigger and better-known cities in Germany's Rhine valley. Dortmund, Schalke and Cologne's stadiums can be reached in less than an hour.

Leverkusen's Lars Bender points on Leverkusen's goalkeeper Lukas Hradecky after their victory in the German Bundesliga first devision soccer match between FC Bayern Munich and bayer Leverkusen 04 in Munich, Germany, Nov 30, 2019. (MATTHIAS SCHRADER / AP PHOTO)

That sense of being outnumbered rubs off on the club, set up 115 years ago as the sports team for the pharmaceutical giant Bayer, whose factories dominate the city of Leverkusen.

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"What always people think is it's hard to play against Leverkusen and you don't like to play against Leverkusen," Jonathan Tah, a defender on the team, told the AP. "They're always aggressive. They're young, they're hungry. They want to be successful. And I think that's the mindset of other teams, what they think about Leverkusen."