The Football Association has rejected Olivier Giroud's red card appeal.
The Arsenal striker was handed his marching orders during the closing stages of his side's encounter against Fulham at the weekend.
Having appeared to slip, the French international then caught Bulgarian full-back Stanislav Manolev on the ankle, which referee Andre Marriner deemed worthy of an instant dismissal.
Arsenal disagreed with the decision and lodged a challenge with the governing body yesterday afternoon.
However, after reviewing the evidence today, the FA have decided to uphold the original decision, meaning that the 26-year-old will now serve a three-match suspension with immediate effect.
He will miss games against champions Manchester United, Queens Park Rangers and Wigan Athletic and will not return until the final encounter of the season away at Newcastle United.