Patrick Vieira said Arsenal's late equaliser was "really tough" to take as his Crystal Palace side were held to a draw in a thriller at Emirates Stadium.
Alexandre Lacazette scored deep into injury time to deny club legend Vieira a winning return, pouncing after Palace failed to clear a corner and Gabriel Martinelli's effort was saved.
The Gunners started brightly and led deservedly through Pierre-Emerick Aubameyang after Vicente Guaita's diving save to deny Nicolas Pepe.
But Palace improved - as the Gunners faded - and Christian Benteke continued his good record in games against the Gunners with the equaliser.