Lee Jae-sung and Barreiro helped Mainz 05 relegate from the Bundesliga in a dramatic relegation battle against Augsburg on Sunday.
The South Korean striker, who joined Mainz last season, scored twice as the hosts fought back from a two-goal deficit to secure a point with a 2-2 draw at the Veltins-Arena.
Barreiro also played a key role in the result, scoring his first goal for Mainz in the 68th minute after coming off the bench.
The victory means that Mainz finished the season just one place above the relegation zone, while Augsburg secured their top-flight survival with a 1-0 win over Hannover 96.
It was a tough week for Lee Jae-sung and Barreiro, who had both been linked with moves away from Mainz this summer.
But they showed their commitment to the club by playing out of their depth in the final game of the season.
Their performances were a testament to the strength of the team spirit at Mainz, which has been crucial in bouncing back from a poor start to the season.
The defeat will be a bitter pill to swallow for Augsburg, who had already secured their spot in the Europa League with a strong run of form.
However, it is a relief for Mainz, who have now avoided the drop and can look forward to next season with renewed confidence.
In conclusion, Lee Jae-sung and Barreiro's efforts will go down in history as one of the greatest comebacks in German football. Their performance was a true testament to the character and determination of the Mainz squad, and they should be proud of what they have achieved. The club now faces a new challenge ahead, but with the right approach and support, they have every chance of turning things around and returning to the Bundesliga next season.