The car manufacturer made the decision to split the business after a final shoot-out between the two agencies.
Ysabel Vazquez, the Mini UK advertising manager, said the decision was made after both agencies presented good creative ideas. "As specialists in digital marketing, we are looking for the agencies to help us illuminate the path forward in what is a very fast-moving market," she said.
Mini previously used the WCRS sister agency Meme for its digital advertising.
The move does not affect Mini's relationship with its direct marketing agency, Lida, which produces websites and online customer communications as part of its direct response brief.
Glue already has some experience working with Mini - it was appointed to handle a one-off project earlier this year, which resulted in the tongue-in-cheek www.aveaword.com website and viral.
Wayne Arnold, the Profero managing director, said: "The news that Profero has been appointed to the Mini account is fantastic. We look forward to working with Mini to drive its digital strategy forward."