After posting softer-than-expected revenue guidance in its fiscal second-quarter earnings, Nike Inc. (NYSE:NKE) is banking on “newness and innovation” to drive growth. However, one analyst struck a discordant note, stating that its fastest-growing piece of business is at risk. What Happened: ‘Just Do It’ might not be working for Nike, but analysts were largely positive on the company’s prospects, with most ratings being “Buy,” “Outperform,” or “Overweight.” However,TD Cowen analyst John Kernan is not as optimistic about Nike’s strategy, casting doubt on the growth prospects of the sneaker make…