Mainz sports director Rouven Schroder concedes a permanent deal for Bojan Krkic is unlikely.
The Stoke City striker is on-loan to the end of the season in Germany.
"Now (a permanent transfer) is not realizable," Schroder said. "It would be beyond our reach economically.
"But at the moment such things are not an issue. First we must hold onto our league status."
Mainz defender Leon Balogun added: "You can see his qualities in training. I'm happy that he could show it in the game."
Source: tribalfootball.com