UPDATE 1-Sports Direct picks RSM UK Group as auditor

(Adds details on Grant Thornton's exit, background)

Oct 23 (Reuters) - Mike Ashley's retail group Sports Direct International said on Wednesday it had appointed RSM UK Group as its auditors, after Grant Thornton abruptly quit earlier this year.

The company had said in August that Grant Thornton, the group's auditor since 2007, would not seek reappointment at Sport Direct's annual shareholders' meeting following a review of its client portfolio.

The British sporting goods retailer had said discussions with other members of the "Big Four" accounting firms had thrown up barriers, including potential conflicts of interest and in the case of PwC a reluctance to engage with Sports Direct.

Sports Direct's results were delayed in July after it received an 11th-hour 674 million euro tax bill from Belgian authorities that had to be assessed by Grant Thornton before it could sign off on the numbers.

In its previous results statement, the British sporting goods retailer said Grant Thornton had "vast experience" of the company and it intended to reappoint the firm for another year. (Reporting by Tanishaa Nadkar in Bengaluru; Editing by Bernard Orr)