* Keith Jones steps down with immediate effect
* Successor could be announced as early as Monday - spokesman
* Company has reported losses since 2009
July 27 (Reuters) - JJB Sports Plc Chief Executive Keith Jones stepped down, leaving his yet-to-be named successor with the task of steering a company that is coping with funding issues, falling sales and stiff competition.
JJB shares were up 5 percent at 5.65 pence at 1420 GMT on the London Stock Exchange on Friday.
The British sports goods retailer, which has appointed U.S. retail veteran Robert Corliss as chairman to accelerate a turnaround program, said Jones would stay in an advisory capacity until the end of August.
Corliss will take over as chairman from Sept. 1.
"They have a new chairman in place. It is highly unlikely that they are going to bring someone from outside," Peel Hunt analyst John Stevenson told Reuters.
A company spokesman declined to comment on media reports that Corliss could take over as chief executive. He said an announcement on a successor could be made as early as Monday.
Jones, who took the helm in March 2010, failed to turn things around at JJB, which has been reporting losses since 2009. Its shares have shed three quarters of their value in the last year.
JJB, whose sales have fallen sharply since April, has been hurt by unusually soggy weather in April and June and an equally damp response to its football jerseys despite the European Football Championship in June.
The Wigan-based company, which operates 180 stores in the United Kingdom and Ireland and employs 4,000 people, has been in talks with its strategic partners to pump in more cash.
The company was brought back from the brink after it received a 20 million pound ($31.40 million) lifeline from U.S. retailer Dick's Sporting Goods in April, and has since been revamping its stores in the UK.
However, it has been left behind by larger rival and aggressive discounter Sports Direct International Plc, owned by Newcastle United football club owner Mike Ashley.