Their guests have it all to play for too with their proud record of top-flight permanence once again on the line going into the final four games of the season. bundesliga.com takes a closer look.
Mainz are one of eight clubs still jostling for a place in the UEFA Europa League next season and their form at the Coface Arena could prove key to their chances. Hamburg will not only be looking to stop them, but also aiming to build on their win over FC Augsburg last week to boost their survival hopes.
is Mainz coach Martin Schmidt's biggest doubt due to a calf strain, meaning is on standby to deputise. Meanwhile, is now back in full training and could be in the squad, albeit on the bench to begin with.
is back after his suspension, but new coach Bruno Labbadia is unlikely to make any changes to the team he sent out for a successful battle a week ago. (l.) is an alternative, though, in place of .
Mainz's most lethal weapon is no longer a secret: midfielder has underlined his set-piece wizardry this season and his mere presence on the field makes conceding a free-kick inside the final third a deadly proposition. Whether it be an assist or a goal, Geis is a guarantee for making something happen within range.
It was a long time in coming, but ended his drought last weekend, chipping in with a second for good measure. That particular burden now lifted, the HSV forward could once again be the man who single-handedly keeps Hamburg in the top flight, just like he did in the closing stages of last season.
Martin Schmidt, head coach: "We're going to have to defend very well, aggressively, compact and determined. We've shown in our recent games that we don't need many chances to score a goal, but first we've got to get the basics right and get ourselves into position in front of the Hamburg goal. That's going to be the key."
Bruno Labbadia, head coach: "We've been preparing for Mainz since Tuesday. We've got to raise our game further. Now's not the time to catch our breath. We're still lacking that bit of self-confidence to get wins – each win takes a great deal of effort. When Rafael van der Vaart says after beating Augsburg that he feels he's just won the league title, then that's saying something."
Two wins in a row have positioned Mainz well for the final four games of the season in which they can really give it a shot for a place in Europe next season, with seventh place potentially good enough. Hamburg ended a dismal sequence of five straight defeats with a win over Augsburg in Labbadia's second game in charge and now they are seeking to build on that.
This will be match number 18 between these two sides, with Hamburg only very slightly ahead on seven wins to Mainz's five. One of those came in the reverse fixture, although Mainz won at the last season and – their first win at home over HSV since 2004.
Mainz: Karius - Brosinski, Bungert, Bell, Park - Geis, Baumgartlinger - Jairo, Malli, Koo - Okazaki
Hamburg: Adler - Westermann, Djourou, Rajkovic, Ostrzolek - Kacar, van der Vaart - Stieber, Ilicevic, Olic - Lasogga