Hamburg leapt into the top six of the Bundesliga with a 1-0 victory at Stuttgart on Sunday, while Eintracht Frankfurt drew 0-0 at Hannover.
Artjoms Rudnevs netted five minutes into the second half to settle a close contest and lift Hamburg a point above Mainz in the final Europa League berth.
In the day's other fixture, Eintracht Frankfurt continued their scoring struggles with a goalless draw at Hannover.
Success for the visitors would have restored them to fourth spot but instead they stretched their goal drought to five consecutive league matches in a stalemate.
