Sports Direct confirmed that Karen Byers, the company’s global head of retail, has left the retailer after 28 years.

Byers joined Sports Direct from fashion chain River Island in 1992 shortly after CEO Mike Ashley founded his retail empire. Ashley has admitted that Byers is the person who runs Sports Direct and former insiders say she is the one who “made things tick and got the best out of people”, describing her as “the glue that holds it all together,” according to the Guardian.

No reason was given for her departure and a replacement has not yet been named.

Michael Murray, the 29-year-old partner of Ashley’s daughter who currently holds the role of “head of elevation” at Sports Direct, is expected to gain further control of the business.

Having begun as a property adviser, Murray is currently heading up the upgrading of the Sports Direct chain, including improving relations with key suppliers such as Nike, Adidas and Under Armour, and also working with its more upmarket Flannels and House of Fraser stores.

The change comes as Sports Direct is integrating House of Fraser, the struggling department store group it acquired in August last year; and also absorbing several smaller acquisitions, including and Evans Cycles.

Ashley said in a statement: “Karen has been a very supportive member of the team for over 28 years and we wish her well for the future. The focus of the business as we move forward remains our program of brand elevation, one that we are totally committed to. The door will always be open to Karen if she wishes to come back to the business as a consultant.”