Mainz will not sell reported Manchester United target Yoshinori Muto, the Bundesliga club have said.
Muto, 23, joined Mainz last summer from FC Tokyo after the German side beat Chelsea to his signature.
The Japan international has been one of Mainz's key players this season, scoring seven goals and creating a further four in 18 appearances for the club.
On Tuesday, Mainz put an end to speculation in Germany that the attacker could leave after only six months and head to United, with the Red Devils reportedly willing to offer €15 million for his services.
"We've put that to bed," Mainz coach Martin Schmidt told kicker.
Also on Tuesday, Mainz pulled the plug on Yunus Malli's transfer to domestic rivals Borussia Dortmund.
The Turkey international, who has scored eight goals this term, and Dortmund had already agreed terms, and both clubs had sorted out the finances of the deal.
However, Mainz were not willing to break up Muto and Malli's partnership, with the pair scoring 15 of their 23 league goals this season.
"We did not want to tear the team apart," sporting director Christian Heidel said.
Last weekend, Mainz suffered a 1-0 defeat at Ingolstadt, and prior to hosting Borussia Monchengladbach on Friday have a six-point lead on Werder Bremen, who sit in the Bundesliga's relegation/playoff place.