West Ham United fear Marko Arnautovic is becoming unsettled by lucrative transfer offers.
The club believe Arnautovic's agent, and brother, Daniel is sounding out potential buyers for the striker.
Arnautovic was the subject of a £35million bid from a Chinese club this month, which the Hammers promptly rejected.
The London Evening Standard has quoted a club source having said: "The agent is trying to create deals to earn money.
"It's not good because it unsettles the player."