West Ham have lost their appeal over the sending-off of goalkeeper Adrian against Leicester and his three-match ban starts immediately.
The goalkeeper will miss the matches with Bournemouth, Liverpool and Newcastle after a wrongful dismissal claim was rejected, the Football Association announced on Tuesday.
Adrian was sent off late in last weekend's 2-1 loss for a challenge on Jamie Vardy after he went up for a corner.
An FA statement said: "A claim of wrongful dismissal submitted by West Ham United in relation to Adrian has been unsuccessful following an Independent Regulatory Commission hearing earlier today. The goalkeeper was dismissed for serious foul play during the game against Leicester City on Saturday (15 August 2015).
"Therefore, the player's three-match suspension, which is the standard penalty for this offence, remains with immediate effect.
"For a club to be successful with a claim of wrongful dismissal, it must prove to an Independent Regulatory Commission via written and/or video evidence that the match referee made an obvious error."
After Saturday's game, Adrian took to Twitter to defend his actions and said he felt his actions did not warrant a red card from referee Anthony Taylor.
Bad result today and worse end of the game.Never in my career I have kicked nobody with bad intention to deserve a red card...neither today!
- Adrián San Miguel (@AdriSanMiguel) August 15, 2015
Summer signing Darren Randolph is the most likely replacement for West Ham, having deputised for much of the Europa League qualifying campaign.
But there may be competition in the form of ex-England goalkeeper Robert Green -- who is reportedly close to returning to his former club from QPR.