West Ham's Aaron Cresswell in action
The hugely influential left-back was hurt in a challenge during Saturday’s pre-season victory over German second tier side Karlsruher SC in Austria.
Cresswell has been a revelation since signing from Ipswich Town for just £3million in the summer of 2014 and is a virtual ever present since then.
Cresswell has been a virtual ever present
Hammers will miss action man
His all action, energetic displays have made him a firm favourite with Hammers fans and he is one of Slaven Bilic's most crucial players both defensively and offensively.
West Ham's head of medical and sports science Stijn Vandenbroucke revealed the bad news on the club's official website on Monday evening.
"(Aaron) will consult a specialist in central London early next week," Vandenbroucke told whufc.com.
"The medical team will then take a decision whether or not the defender requires surgery.
“Whatever course of action we decide to take, Aaron faces a period of rest, followed by treatment and rehabilitation and he will be out for a period of between three and four months."
Aaron Cresswell celebrates
Cresswell reacted to the news by posting a message on Twitter simply saying: "Absolutely devastated," along with a picture which reads 'Never let a stumble in the road be the end of the journey'.
Absolutely devastated.. ⚒ pic.twitter.com/AOQuhuyKBC— AARON CRESSWELL (@Aaron_Cresswell) July 25, 2016
And Hammers supporters haven't taken the news too well either, venting their frustrations and commiserating their star player on the social networking site.
@Aaron_Cresswell I hear you! Your be back flying in no time at all!— Matt Jarvis (@MrMattJarvis) July 25, 2016
@Aaron_Cresswell he wears the magic hat! Positive thinking Azza, nothing but love from all of us at the club from Owners to us gobby fans! ⚒— Baz Cox ⚒ (@Baz1980WHU) July 25, 2016
@Aaron_Cresswell chin up mate, you're the best LB in the country & you will be back stronger than before! We're all in it together ⚒⚒⚒— SexDrugs&CarltonCole (@S_D_C_C) July 25, 2016
IPSWICH TOWN FANS (@IpswichTownFans) July 25, 2016