(Reuters) - Best Buy Co Inc reported a weaker-than-expected profit and its ninth same-store sales decline in 10 quarters, highlighting the challenges its new chief executive officer faces in trying to turn around the world's largest consumer electronics chain.

The retailer, which faces cutthroat competition from the likes of Amazon.com Inc , Wal-Mart Stores Inc and Apple Inc , said its net loss in the third quarter ended on November 3 was $13 million, or 4 cents a share, compared with year-earlier net earnings of $173 million, or 47 cents a share.

Excluding restructuring charges, the company earned 3 cents a share, far below the analysts' average estimate of 12 cents, according to Thomson Reuters I/B/E/S.

Sales at stores open at least 14 months fell 4.3 percent, including a 4 percent decline at the company's U.S. unit.

The news came just days before the unofficial start of the holiday season and amid a wide organizational restructuring under new CEO Hubert Joly and a looming buyout proposal by founder Richard Schulze.

Last month, the retailer had warned that earnings and same-store sales would show declines for its third quarter.

(Reporting by Dhanya Skariachan; Editing by Gerald E. McCormick and Lisa Von Ahn)