Diafra Sakho is out of action for three months, the official West Ham website has confirmed.
The forward picked up an injury last weekend, and has consulted a specialist to see the true state of the severity of the problem.
He has an issue with his thigh, and the Senegalese forward is set to undergo surgery this Saturday on the first step of his recovery.
However, he is not set to return until the New Year, with the report confirming an almost three month recovery time is needed by the 25-year-old.
With Enner Valencia also out of action, Slaven Bilic has to turn to either Andy Carroll or Nikica Jelavic this weekend, with the Hammers taking on Manchester United at Old Trafford.
The loss of Sakho deals a real blow to West Ham’s seasonal aims, having started the campaign so well.
The forward is perfectly suited to the Hammers’ style of play, and although his goalscoring has not been as good as it was last term, his work rate, athleticism and desire are second to none in Bilic’s squad.
Having lost Dimitri Payet to injury, losing Sakho has caused frustration to a number of West Ham fans, and we collect some of the best reactions to the confirmation of the forward’s three month absence.
Payet out for 3 months and now Sakho out for 3 months too......no bother, they'll be back in time to keep us up! #whufc— Dan Hill (@danjameshill) December 4, 2015
Sakho out for 3 months and undergoing surgery on Saturday. Kill me.— Nina Verma (@Niiinnnaaa_) December 4, 2015
Sakho out for three months won't have our best eleven till March #WHUFC— Jack Peters (@JackPeters_) December 4, 2015
What are we gonna do without Sakho...— Kye (@Kye_WHU) December 4, 2015
Sakho injured for 3 months— Sean Fennell (@SeanFennell5) December 4, 2015
Sakho 3 months, season over. Fast forward to next season please.— Charlie Hatt (@Chas_Hatt) December 4, 2015
Sakho out for 3 months. What is life— alex (@AlexFynn) December 4, 2015
No worries about Sakho. @AndyTCarroll going to score for next 12 games, have an even bigger party and win golden boot in France next summer— Luke Williams (@LukeyWills_) December 4, 2015
hahaha season over Payet and Sakho out for 3 months and Valencia not back until the New Year— BenSelf (@BenSelf96) December 4, 2015
Losing both Sakho and Payet for 3 months has destroyed our season.— Lloyd Bowman (@lbowman6) December 4, 2015
Sakho out for 3 months,don't be surprised if Adebayor don't turn up soon,all this we have no wages we released Amalfitano so that's bollocks— ⚒ AL ⚒ (@6_AaronLee) December 4, 2015