The USMNT international was Bremen coach Florian Kohfeldt's secret weapon on Saturday evening, and he needed just two minutes to make an impact and help secure another three points after influencing two wins in Bremen's previous three Bundesliga matches.
With just minutes to go of a relegation six-pointer, Johannsson leapt from the bench, replacing captain Zlatko Junuzovic. His impact was instant. Within moments, his shot could not be kept out by either Hamburg goalkeeper Christian Mathenia or defender Rick van Drongelen, who managed only to bundle the ball over as he tried desperately to clear.
As a result of those nine points out of a possible 12, Bremen can breathe a little easier for the rest of the week with nine points now separating them from their northern Germany rivals Hamburg after a crucial win at the Weser-Stadion.
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"This win is extremely significant," said Kohfeldt. "This was an important win for Werder Bremen and this city, and I don't think it was undeserved either."