But after reviewing video evidence Riley has decided Cisse's challenge did not warrant a second yellow card.
A statement issued on the FA website confirmed: "Following the Arsenal versus Birmingham match on Sunday, match referee Mike Riley has reviewed the sending off of Aliou Cisse.
"He has decided that the tackle was careless and warranted a free-kick rather than reckless which he thought at the time and has asked that the second caution should not be issued.
"Therefore it has been agreed that the player will have a caution recorded against him for the first offence and will not have to serve a one-match suspension."