Arsenal is now suffering a major blow ahead of Manchester on Saturday.
This has happened after midfielder Lucas Torreira banned for three games after the Football Association rejected Arsenal’s appeal over his red card against Tottenham.
Torreira, on as a half-time substitute, saw red in the fifth minute of stoppage time, after his stud-showing follow-through caught Danny Rose high on the shin.
The 23-year-old will now miss United’s visit to the Emirates Stadium on Sunday, as well as the visit of Newcastle and a trip to Everton.
The United game, in particular, looks critical, with both sides part of a race with Chelsea and Tottenham for two Champions League spots.
It was one of a number of blows for Arsenal in the 1-1 north London derby draw, with Harry Kane equalising for Tottenham through a controversial penalty after Aaron Ramsey had opened the scoring.
They still had a chance to win the derby late on, when Davinson Sanchez felled Pierre-Emerick Aubameyang, but the Gabonese saw his spot-kick saved by Hugo Lloris in the 90th minute.
Torreira will next be available for the trip to Watford on April 15