Arsene Wenger has confirmed Olivier Giroud will miss Arsenal's Champions League second-leg clash with Besiktas on Wednesday 27 August.
French international Giroud suffered an ankle injury in the dying minutes of Saturday's 2-2 draw with Everton after scoring his side's late equaliser at Goodison Park.
The striker's knock prompted fears he could be ruled out for up to three months, a situation that would surely force Wenger back into the transfer market to find adequate cover up front.
Speaking to the press ahead of Wednesday's clash at the Emirates, Wenger confirmed his striker's absence ahead of their play-off decider but was unable to confirm the length of the injury.
He told reporters: "Oliver Giroud will not play tomorrow, we will see a specialist. It can be [a long injury] but we will see tomorrow."
In recent days, there has also been speculation surrounding the future of another of Wenger's forwards in Lukas Podolski. The German's agent recently announced there was "concrete interest" in his client's services, prompting reports the Gunners were prepared to hold talks with Juventus regarding the player's possible sale.
However, with just six days of the transfer window remaining, Wenger appeared unprepared to allow the World Cup winner to leave the Emirates, telling reporters: "Podolski is in the squad tomorrow and will stay with us."
Arsenal's hopes of qualifying for their group stages of the Champions League once again hang in the balance after they were held to 0-0 draw in Turkey last week.
The Premier League club will also have to find a way through Besiktas without the influence of Aaron Ramsey, who will serve a suspension after being shown to yellow cards in the first-leg clash.