Oct 1 (Reuters) - Nike ( NKE ) posted a

bigger-than-expected drop in first-quarter revenue on Tuesday,

as the sportswear giant battles weak demand in key market China

and faces stiff competition from newer brands globally.

The company's first-quarter net revenue fell to $11.59

billion from $12.94 billion a year earlier. Analysts had

expected a 10% fall to $11.65 billion, according to analysts'

estimates compiled by LSEG.