The agency will now take responsibility for Powerade's TV, print and outdoor advertising in the region. The win secures Fallon a place on the Coca-Cola roster.
Mother, which picked up the Powerade account in May 2007, will continue to work on the existing Powerade "innergear" print and outdoor campaign that promoted the brand's association with the Beijing Olympics.
The ads featured British athletes such as the triple-jumper Phillips Idowu and the cyclist Rebecca Romero performing naked.
Fallon's appointment is the latest in a number of changes to Coca-Cola's marketing arrangements, resulting from a shift in advertising strategy from a market-by-market approach to regional briefs.
The soft-drinks giant moved the pan-European advertising account for Sprite to Ogilvy & Mather Frankfurt in July, before shifting its pan-European Coca-Cola and Diet Coke ad briefs into Mother later in the summer. The agency already handled advertising for a number of other Coca-Cola brands such as Schweppes and Oasis.
A spokeswoman confirmed that Coca-Cola had "enlisted Fallon to explore creative work across Europe on Powerade".