The 19-year-old midfielder was brought on as a late second-half substitute with the Hammers trailing 2-0 at the London Stadium. However, his afternoon was cut short after accidentally colliding with teammate Edson Alvarez.
Earthy fell in a worrying manner, prompting medical staff to rush onto the pitch to treat him. He was then stretchered off after six minutes of treatment on the pitch, during which he required oxygen.
A statement confirmed that he is awake and has been taken to the hospital for further assessment. West Ham United will provide a further update in due course.
A product of the Irons’ academy, Earthy was part of the West Ham U18 side that won the FA Youth Cup and the U18 Premier League South last season. The teenager made his first-team debut as a late substitute in the 5-0 away win at Freiburg in the Europa League last 16 second leg last month.