Arsenal have been dealt a blow in their chase for the top-four of the English Premier League after the F.A. rejected Arsenal's appeal for the red card received by Olivier Giroud in their game against Fulham at the weekend.

Giroud received a straight red from referee Andre Marriner, for a tackle on Stanislav Manolev, which Arsenal decided to appeal claiming the striker had slipped on his way through to the tackle.

However, the F.A. rejected the appeal and Giroud will now serve a three-match ban, which means he will miss the Premier League games against Manchester United, Queens Park Rangers and Wigan Athletic.

The Frenchman will be available for Arsenal's final game of the season against Newcastle United.

"Following an Independent Regulatory Commission hearing today (Tuesday), Arsenal's Olivier Giroud has had his claim for wrongful dismissal rejected," the F.A. said in a statement.

"Giroud was dismissed for serious foul play during his side's game against Fulham at Craven Cottage on Saturday 20 April, 2013.

"The player's three-match suspension will therefore commence with immediate effect."

Arsene Wenger will now have to decide on the player who will lead the line for the next three games, with the Frenchman set to pick from one of Theo Walcott, Lukas Podolski and Gervinho.

Meanwhile, Arsenal defender Laurent Koscielny believes he is at his best when involved in a physical duel with the opposing team's striker.

"I need to have duels and win them," he told the club's official website. "It's better for my game because I am more confident, I can take little risks with passes and feel better and better during the game.

"Now it's up to me to keep this all the time. I'm in a good position because I'm fit and I'm confident. I think every player wants to finish high up in the table. I will give everything for the squad to finish in the Champions League places."

Koscielny was in and out of the team earlier in the season, after a few niggling injuries kept disrupting his form.

However, in the last couple of months the French international has greatly benefited from a good run-in the team, and believes the injuries might have worked in his favor in him finding form towards the end of the season.

"When you are injured, it's very difficult because you need time to be fit," he said. "I needed to come back and play a lot of times to be fit and confident on the pitch.

"It was difficult but it's good for my career and my body. I think it can help me for the next season and for more years."