Arsenal are facing a defensive crisis for the FA Cup final after Laurent Koscielny's appeal for wrongful dismissal was rejected by the Football Association.
The 31-year-old centre-back received his marching orders just 14 minutes into the Gunners' 3-1 win over Everton on the final day of the Premier League season on Sunday.
Koscielny was shown a straight red card after he caught Toffees winger Enner Valencia with a late sliding challenge, with Arsene Wenger's side 1-0 up at the time.
Worse was to follow for the north Londoners as Gabriel left the pitch on a stretcher early in the second half with what appeared to be a bad knee injury.
Per Mertesacker replaced the Brazilian having previously not kicked a ball the entire campaign, and the German could be handed an unlikely start against Chelsea at Wembley on Saturday with compatriot Shkodran Mustafi nursing a head injury.
The Gunners were hoping for leniency from the FA as Koscielny's tackle on Valencia was not a dangerous one, but their appeal failed and the France international will serve a three-match ban – ruling him out of the showdown under the famous arch this weekend.
"Laurent Koscielny will serve a three-match suspension with immediate effect after a claim of wrongful dismissal was unsuccessful," read a statement from English football's governing body.
"The Arsenal defender was sent off for serious foul play during the game against Everton on Sunday [21 May 2017]. An Independent Regulatory Commission heard the case today [Tuesday 23 May 2017]."