Borussia Dortmund attacking midfielder Shinji Kagawa is set to reject a new deal at the German champions and instead looks set to move to England.
The 23-year-old has turned down an extension to his current deal, which would have seen his wages double.
With a year to run on his contract, Kagawa could leave the club for nothing come the end of next season, therefore could be offloaded this summer.
"There should be a decision soon. We would like to extend with him," Zorc told Bild.
"The ball is in [Kagawa's] box - Shinji must now decide. We know that he is flirting with clubs in England and Spain."
Kagawa has been heavily linked with a move to Manchester United in the past, and would provide an additional option in midfield alongside the likes of Michael Carrick and Paul Scholes.
The Japan international's haul of 13 goals in 31 appearances this season has clearly attracted the attention of United, who are closing in on a record 20th league title.
Furthermore the signing of Kagawa would further enhance United's standing in Asia, a market the club have continually exploited.
After spending in excess of £50 million last summer, United's transfer plans are expected to be limited. However, if available, Kagawa could become their sole summer signing.