West Ham youngster Dylan Tombides as died at the age of 20 from testicular cancer.
He was first diagnosed with the condition in 2011, but went on to make his first team debut in their League Cup tie with Wigan in September 2012.
The Australian-born striker passed away this morning.
A minute's applause will be held ahead of West Ham's Premier League match with Crystal Palace tomorrow and the team will wear black armbands in his memory.
STATEMENT: West Ham United announce the sad news that Dylan Tombides has passed away at the age of 20. http://t.co/bcBIElzRrr
— West Ham United FC (@whufc_official) April 18, 2014