Elliott Hill, the newly named chief executive officer of Nike, acknowledged that things have been rough for the world's largest sportswear brand in his first message to staff on Thursday.

When Nike said on Thursday that John Donahoe was stepping down as chief executive officer, his exit from a rocky tenure offered a brutal reminder to corporate boards: Focus on what a company's core business is when looking for a new CEO.

Nike spent nearly $104 million on pay and benefits for John Donahoe during his near five-year tenure atop the sneaker-maker, before replacing the former Bain & Co. executive in a bid to revive the brand.