Per Mertesacker says referee Jonathan Moss failed to explain his decision to allow Nottingham Forest's controversial second penalty to stand as Arsenal were knocked out of the FA Cup.
With the holders chasing an equaliser at the City Ground, Mathieu Debuchy was judged to have fouled Armand Traore inside the area and Kieran Dowell appeared to slip and touch the ball twice when taking the resulting spot kick.
Gunners keeper David Ospina and a number of Arsenal players immediately rushed to the referee in the hope of the goal being ruled out and a free-kick awarded in their favour.
Referee Moss discussed the incident with his assistant, despite the protests, allowed the goal to stand.
"Yes [it was a double contact]," Mertesacker insisted to the club's official website.
"It would’ve been a free-kick for us. You could clearly see it, that’s why we shouted to the referee.
"He didn’t have any explanation and that’s on him.
"They obviously spoke to each other, and nobody saw the incident.
"David saw it and all the players did too."
