Sky Deutschland is owned by Sky Plc, which has just been taken over by Comcast in a $40 billion deal. DAZN, part of tycoon Len Blavatnik's Perform Group, is positioning itself as the 'Netflix of sport'.

The Federal Cartel Office said in a statement announcing the investigation that Sky had acquired rights from European soccer governing body UEFA to broadcast all Champions League games from 2018-21.

It then reached an agreement with DAZN to share the slate of matches, meaning that from this season no Champions League soccer can be watched on terrestrial TV in Germany.

"We are investigating whether and in what form the cooperation between the two companies was agreed, and whether it has served or hindered the interests of consumers," cartel office President Andreas Mundt said in a statement.

In that context the cartel office also said that Sky, as Germany's leading Pay-TV operator, is subject to particular restrictions in cooperating with competitors, and that the deal with Perform may serve to strengthen its market position.

Sky Deutschland said it had been informed by the cartel office about the investigation and would cooperate fully, but declined to comment further.

No comment was immediately available from Perform Group, whose DAZN sports streaming service operates in Germany, Austria, Switzerland, Japan and Canada.

(Reporting by Douglas Busvine; Editing by Michelle Martin)