Grey and Saatchi & Saatchi are fighting it out to hire David Patton, Sony's senior vice-president of communications for Europe, to fill their vacant chief executive roles.
Grey has already offered the role to the high-profile Sony marketer, but he is also one of three candidates that has been shortlisted for the CEO job at Saatchi & Saatchi.
Kevin Roberts, Saatchis' worldwide chief executive, is due to fly in and vet the final candidates this week.
Grace Blue, the headhunting company set up by Gay Haines, is thought to have put Patton forward for both roles.
The role at Grey became available in January this year, when the former chief executive, Tamara Ingram, left the post to take on the leadership of the $1 billion global Procter & Gamble account.
The Saatchis job came up for grabs a month later when Lee Daley, the chairman and chief executive, departed the agency to become the global commercial director at Manchester United Football Club.
Patton is famed for being particularly sensitive to the creative process and was the client behind the lauded "balls" ad for Sony Bravia. He also sanctioned "mountain", the Sony PlayStation ad created by TBWA\London that picked up the Grand Prix at Cannes in 2003.
Patton joined Sony in 1995 as the vice-president of marketing for Sony Computer Entertainment.
In March 2004, Patton was promoted to his current role, which saw him become solely responsible for the PlayStation brand across Europe. Since then, Patton's remit has steadily expanded to include all of Sony's products across Europe.
The promotion also saw Patton working closely with Chris Deering, the chief executive of Sony Europe, to spearhead the revival of the electronics brand, which had seen its sales slump prior to Deering's appointment.
Both Saatchis and Grey refused to comment. Patton was unreachable as Campaign went to press.