Well, now that the rugby games have been cancelled, I can offer you another alternative.
On Sunday 3rd will take place the Burkhard-Mentz-Memorial, a quick chess tournament organized by the Findorffer Schachfreunde. For most people thinking that chess is a very boring game... well, you are essentially right, but quick chess is quite different. It is definitely more active than standard chess although not as spectacular as blitz, but lots of games will certainly finish with high-tension blitz-endings.
Around 80 players use to take part in this tournament, including some IM and FM but mostly amateurs with a varied playing strength. It is an open, so anyone can join (if interested, see details at Protected content or Protected content , or you may just drop by to have a look.
It starts at 9:45 and will finish at around 18:00, and it will be held at Konferenzzentrum Radio Bremen, Weserhaus, Hinter der Mauer 5-7, 2. Etage (tram stop VHS-Radio Bremen on lines 2 and 3, or three minutes on foot from Am Brill)