Arsenal chief executive Ivan Gazidis was last night thrashing out the finer details of the deal with Emery's representatives.
Emery was axed from his role as Paris Saint Germain manager at the end of last season, with Thomas Tuchel taking his position in the French capital.
The news was met with shock from players on Monday night, who had fully expected Arteta to be in charge next season.
But news started filter through among the playing staff from around 4pm of Emery's imminent appointment.
Gazidis and director Josh Kroenke had been set on handing the job to a younger coach with fresh ideas.
So the move for Emery comes as something of change of heart; the Spaniard coming with vast experience during his time with Sevilla and PSG.
Arteta was set to sign a three-year deal worth £4 million a year, and it's believed the former Arsenal and Everton player would have accepted the job.
Arsenal insisted on Monday night that they had not got cold feet over offering the job to Arteta, insisting they were fully committed to the process of identifying Wenger's replacement.
UNAI EMERY
Born: Hondarribia, Spain, on November 3, 1971
PLAYER
Started at Real Sociedad, playing five La Liga games at left wing before making his name with Toledo in the second tier, where he would spend the bulk of his career.
MANAGER
2005-06 Lorca Deportiva
Promotion to second division for first time in club's history
2006-08 Almeria
Promotion to top flight for first time in club's history
2008-12 Valencia
Achieved three successive third-place La Liga finishes
2012 Spartak Moscow
Lasted six months
2013-16 Sevilla
Won three successive Europa League trophies
2016-18 Paris Saint-Germain
Won the domestic treble
Managerial career
P: 719, W: 385, D: 155, L: 179. Win: 53.5 per cent
FULL HONOURS
Sevilla
Europa League (x3): 2014, 2015, 2016
Paris Saint-Germain
Ligue 1: 2017-18
French Cup (x2): 2017, 2018
French League Cup (x2): 2017, 2018
French Super Cup (x2): 2016, 2017