Arsenal take on Chelsea at Wembley this weekend with the Gunners looking to end the season on a high with some silverware after missing out on Champions League football.
But Wenger has been hit with an injury crisis at the back ahead of their meeting.
Gabriel has been ruled out for up to eight weeks with a knee ligament injury, while Shkodran Mustafi is yet to train after illness.
Kieran Gibbs is not back in training after a thigh problem and Laurent Koscielny is suspended.
That leaves Rob Holding as Wenger's only fit centre-back at his disposal.
Per Mertesacker could return to the starting lineup for Arsenal on Saturday Arsenal line-up predicted to face Chelsea in FA Cup final Thu, May 25, 2017
Click to reveal the Arsenal line-up predicted to start against Chelsea in the FA Cup final
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GK: Petr Cech
I haven’t played this year. But I have done this for 15 years so I expect myself to be absolutely ready no matter what comes.
However, Mertesacker could make only his second appearance of the season if he is fit after coming off the bench against Everton last weekend.
He last played 90 minutes for Arsenal back in April 2016.
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Asked if he would be ready if selected by Gunners manager Arsene Wenger, Mertesacker responded: “I cannot tell you.
“I haven’t played this year. But I have done this for 15 years so I expect myself to be absolutely ready no matter what comes.
Arsene Wenger is short of options at the back ahead of Arsenal's FA Cup final showdown with Chelsea
“That is my mindset, no matter what happens or what is facing me on Saturday, I am going to go for it. I owe this to this team and to this club.
“I want to make sure I will be ready and my mindset is ‘120 minutes plus penalties’.
“(It is) completely unexpected. I made the squad because of two injuries and then I came on (on Sunday in the 3-1 defeat of Everton) due to one red card and one injury.
“It was unexpected but you need to be ready at any time. It was good to get a run out and obviously make my first appearance of the season after a long, long injury. I was very grateful I got the opportunity.”