Zlatko Junuzovic, who had earlier rattled the post with a free kick, took full advantage of a similar opportunity later in the first half by picking out the top corner to level the scores.
After responding well to equalise, the hosts took the lead in spectacular fashion early in the second half as Melvyn Lorenzen cut in from the left wing before firing an unstoppable effort into the bottom corner.
However, their joy was short lived as Hannover hit back to take the lead with two goals in two minutes just after the hour mark.
Hiroshi Kiyotake started the spell as provider as he sprinted into the box before crossing to Joselu, who converted from close range.
The Japanese midfielder then put his side 3-2 up when his delivery from a free kick somehow managed to miss the bodies in the area before finding the bottom corner.
An inevitable spell of Bremen pressure arrived in the closing stages, but it looked as if the home fans would be left disappointed as Viktor Skrypnyk's side struggled to create clear-cut chances.
The frustration finally came to an end when Alejandro Galvez found the space from which to deliver an inch-perfect cross into the box, which allowed Selke to tap home the equaliser from close range.