The Gunners continued their impressive start to the season, having secured a 2-0 victory on Saturday at the Stadium of Light.
Sunderland were given the chance to take the lead from the spot in the 55th minute, but Enzo Le Fee's penalty was brilliantly saved by David Raya, who tipped the ball onto the post.
The momentum swung decisively in Arsenal's favour just three minutes later when Bruno Guimaraes found the net to open the scoring before Bukayo Saka sealed the 2-0 win.
Arsenal to escalate penalty decision with formal complaint
Despite winning the match, the Gunners are said to be frustrated with the decision against defender Ezri Konsa and are demanding clarity on the officiating process.
According to reports, Arsenal will formally contact Pro Ref following the incident at the Stadium of Light.
The controversy arose when referee John Brooks penalised Konsa for holding Sunderland captain Dan Ballard inside the box.
The decision was upheld by the Video Assistant Referee (VAR), much to the dismay of the North London club.
The Premier League Match Centre later issued a statement confirming the on-field call, explaining: "The referee's call of penalty to Sunderland for a holding offence by Konsa on Ballard was checked and confirmed by VAR."
However, replays appeared to show a mutual physical contest between the two players, fuelling Arsenal's sense of injustice.