Stoke forward Marko Arnautovic has handed in a transfer request, Press Association Sport understands.
The 28-year-old has asked to leave the bet365 Stadium with West Ham interested in signing him.
Arnautovic, who only signed a new four-year deal at Stoke last summer, is currently with the squad in Switzerland for their pre-season training camp.
Stoke have made no decision over the request and Arnautovic is due to play against Neuchatel Xamax on Monday as the Potters kick off their pre-season programme.
The Austria international was linked with Everton last year before signing his new deal and Stoke would be unwilling to have another transfer saga.
With the current inflated transfer market Arnautovic would be expected to command a large fee should Stoke even be tempted to sell.
Arnautovic joined from Werder Bremen in 2013 and has made 145 appearances, scoring 26 goals, for the Potters. He netted seven times in 35 games last season.
Stoke are already chasing Manchester City midfielder Fabian Delph as they look to reshape their squad following last season's 13th placed finish in the Premier League.
