Sept 20 (Reuters) - Basketball great Michael Jordan will increase his investment in Sportradar Group AG and will serve as a special adviser to the company's board, the sports gambling data company said on Monday.

The company's shares rose 3.4% in extended trading.

Switzerland-based Sportradar went public last week via the initial public offer route after abandoning plans for a merger with a special purpose acquisition company earlier this year.

The company did not provide details regarding Jordan's increased stake but said his advisory duties will revolve around the U.S. market, product development and marketing activities.

Jordan, a six-time NBA champion with the Chicago Bulls in the 1990s, was an early investor in Sportradar. He also joined sports-betting firm DraftKings as a special adviser in September last year.

Sportradar provides software, data and content through subscription and revenue share arrangements to sports leagues, betting operators and media firms. Its customers include DraftKings, Twitter and ESPN.

(Reporting by Uday Sampath in Bengaluru; Editing by Krishna Chandra Eluri)