Hannover sporting director Dirk Dufner is fighting a battle to keep custodian Ron-Robert Zieler at the Bundesliga club, with a release clause hanging over the 24-year-old.

Zieler can quit Hannover this summer if a bid of around €8m lands on the club's desk by 1st May. Now Dufner wants to remove that clause, according to German daily Bild, and increase the 24-year-old's contract length from its current expiry date of 2015.

The highly-rated goalkeeper is angling for a large salary increase if he is to remove the clause from his contract. But talks could be complicated by interest in Zieler and his desire for European football.

Liverpool were confirmed as having their eyes on Zieler over the summer, while the former Manchester United youth goalkeeper remarked last month: "I would love to play in European competition and establish myself at international level."

Hannover finished ninth in the Bundesliga last season and face a battle to show Zieler that he can realise his European ambitions at the club.

Presently Hannover sit eleventh in the Bundesliga, having accumulated 14 points from 12 games.

Source: InsideFutbol