Salzburg had a 1-0 lead after last week's meeting in Strandvallen, so the pressure was on the Sölvesborg team.
But the dream was dashed by the home team's Karim Konate. After a goalless first half, Salzburg stepped up and Konate scored both 1-0 and 2-0 within a few minutes of each other early in the second half before Haris Tabakovic completed the scoring in the 80th minute.
The loss means that Mjällby will now play in the Conference League instead, which gives the club the equivalent of approximately SEK 35 million in guaranteed income, around SEK 12 million less than the Europa League.
