After five matchweeks of the German top flight, St Pauli are in 14th place with four points and won 3-0 against Freiburg on September 28, while the visitors have one point more in 12th place and lost 2-0 against Heidenheim last Saturday.
Match preview
The hosts had lost their first three league games of the season and drawn their fourth against RB Leipzig, scoring just once in that period.
However, St Pauli managed to score three times against Freiburg from just over one xG, although they could have easily conceded had Freiburg converted the penalty they missed in the 41st minute when the score was 1-0.
Kiezkicker manager Alexander Blessin said in the aftermath of his team's win that he hoped his side are able to be as competitive as they were against Freiburg for the remainder of the season.
The result means that St Pauli have now collected four points from their last two league games, and are three points clear of the 17th-placed Bochum, who occupy the first of two automatic relegation spots.
Blessin's team conceded six goals in their first three league games but have kept two clean sheets in their last two Bundesliga matches, although they have failed to win their two top-flight home fixtures this term.
As for the visitors, they come into the clash having lost against Heidenheim, a match in which Mainz centre-back Andreas Hanche-Olsen was sent off after just 28 minutes when his side were trailing 1-0.
While Mainz might argue that the red card meant they had little chance of getting a positive result, their loss means they have drawn two, lost two and won just once in their last five competitive games.
To their credit, the away side did beat Augsburg 3-2 on September 20 despite being forced to play with 10 men from the 35th minute, and they have lost just twice in their last 14 league matches.
Boss Bo Henriksen will believe that his team can at least avoid defeat on Saturday given his side have won two and drawn four of their six most recent away games in the top flight, though they drew eight and lost nine of their last 17 fixtures on the road.
Henriksen may be concerned about his team from an offensive perspective seeing as his team rank 13th of the 18 Bundesliga sides for chances created, as well as 14th for xG produced.
St Pauli Bundesliga form:
L
L
L
D
W
St Pauli form (all competitions):
W
L
L
L
D
W
Mainz 05 Bundesliga form:
Mainz 05 form (all competitions):
W
D
D
L
W
L
Team News
The hosts will be without midfielder Carlo Boukhalfa until late October, as well as goalkeepers Sascha Burchert and Soren Ahlers, until the middle of the month.
Strikers Maurides and Simon Zoller are also likely to miss out until later in the month, but St Pauli have an otherwise healthy squad.
Blessin could name a largely unchanged XI from the side that beat Freiburg, so expect Hauke Wahl, Eric Smith and Karol Mets to start as centre-backs.
Oladapo Afolayan, Johannes Eggestein and Elias Saad will likely be selected in the forward line.
Mainz will be unable to select Andreas Hanche-Olsen, who is suspended, while Nikolas Veratschnig could be available in the coming days.
Henriksen could replace Hanch-Olsen in defence with Dominik Kohr, and he may be partnered by fellow centre-backs Moritz Jenz and Anthony Caci.
In midfield, the visitors could start Kaishu Sano and Nadiem Amiri as a double pivot behind forwards Hyun-Seok Hong, Jae-sung Lee and Jonathan Burkardt.
St Pauli possible starting lineup:
Vasilj; Wahl, Smith, Mets; Saliakas, Irvine, Metcalfe, Treu; Afolayan, Eggestein, Saad
Mainz 05 possible starting lineup:
Zentner; Kohr, Jenz, Caci; Widmer, Sano, Amiri, Mwene; Hong, Lee; Burkardt
We say: St Pauli 1-1 Mainz 05
Although the hosts have been in better form of late, they have only scored four goals in the league and it would be surprising if they scored many on Saturday.