Britain's biggest sporting goods retailer Sports Direct said on Thursday it had promoted Matt Pearson to be chief financial officer, 18 months after its last CFO retired.

Sports Direct, founded and majority controlled by Newcastle United soccer club owner Mike Ashley, has faced criticism from top five shareholders Odey Asset Management and Standard Life over its slow response to replacing Bob Mellors, who retired in December 2013 on health grounds after almost a decade as CFO.

Pearson, who joined Sports Direct as an accountant from EY in June 2007 before being appointed group financial controller, will join the board immediately, the company said.

"After a thorough process and following soundings from leading institutions I am delighted that Matt has been appointed Acting Chief Financial Officer and is to join the board," Sports Direct Chairman Keith Hellawell said.

Shares in FTSE 100-listed Sports Direct, which pays its executives relatively low base salaries bumped up by performance related share bonuses, were flat in early trading at 683 pence.

The shares are down 11 percent on a year ago, in part due to disappointment around slow progress on acquisitions needed to fuel big expansion plans in Europe.