Mainz have taken Brazilian midfielder Andre Ramalho on loan from Bundesliga rivals Bayer Leverkusen for the rest of the season.
Ramalho, who joined Leverkusen from Salzburg a year ago, has been drafted in as additional cover for the injured Danny Latza.
"I am delighted to be joining Mainz," the 24-year-old told the club's official website. "Mainz have convinced me as a club, and I want to prove myself here this season.
"We have high expectations for the season and it is certainly not going to be easy, but I am sure we will be successful and I want to play my part in this."
Mainz sporting director Rouven Schroder added: "With Danny Latza still out, we wanted another German-speaking player for our defensive midfield.
"We gain more stability in the centre of the field with Andre Ramalho, who can also play in the full-back position, is aggressive, robust, energetic and has a great positional game, in addition to having a very good character and being a team player."