Incumbents BBDO and Saatchi & Saatchi missed out on the US$200 million creative accounts.
Wieden & Kennedy has created the work.
The agency employs more than 1,500 staff across eight offices.
Ad aired ahead of basketball star's memorial service.
“I hate to be harsh, but someone else's tragedy can be our opportunity,” David Luhr said.
Wieden+Kennedy's first campaign for the brand treads a different path from typical shampoo advertising.
Top news, insights and analysis every weekday
Sign up for Campaign Bulletins