In the last year, shares of Under Armour (UA) are down 26%. Investors are wondering whether Under Amour can get back in the game.

Almost 24% of Under Armour shares are sold short. Hedge funds torpedoed the stock after The Sports Authority filed for bankruptcy. On May 31, Under Armour cut fiscal 2016 guidance and said it would take an impairment charge of approximately $23 million related to the liquidation. Of the estimated $163 million worth of sales Under Armour expected to come from Sports Authority, management said it would only recognize $43 million of revenue, which means that Sports Authority was just 3% of Under Amour's revenue.

Under Armour cut full-year guidance by $75 million to $4.95 billion. The guidance assumes other retailers will pick up the slack from Sports Authority's bankruptcy as customers look for Under Amour at other outlets.

Even with the guidance cut, Under Armour is still expected to grow top-line revenue by 24% in fiscal 2016.

Under Armour reported second-quarter results at the end of July. Revenue rose 27.7% to $1 billion, in line with expectations. Gross margin dropped to 47.7% from 48.4%, primarily driven by a slightly less profitable sales mix. Wholesale revenue grew 27% to $635 million, while direct-to-consumer grew 28% to $321 million. International revenue, which is just 15% of total revenue, grew 68%.

Apparel was up 19% to $613 million. Footwear jumped 58% to $243 million, reflecting the continued success of the Steph Curry basketball line. Accessories increased 21% to $101 million.

Management said third-quarter revenue would be up 20%. Operating income would be in the range of $180 million to $185 million, representing 5% to 8% growth. Revenue is expected to grow 20%. That works out to about $1.45 billion in revenue. Some investors felt guidance was disappointing, because they thought the company would bounce back faster after Sports Authority's liquidation. Last year, the third quarter grew by 28.4%.

With a lackluster third quarter, the pressure is really on in the fourth quarter. The first half of the year grew by 28.9%, and it looks like the back half is only going to grow by about 21%. That's a pretty steep slowdown, especially when you compare 2015 to 2016. The second half of 2015 grew by 29.6%. Last year, fourth-quarter revenue was up almost 31%. The fourth quarter this year will probably be up just 22%.

Now you know why the stock is so heavily shorted. Growth fell off a cliff in the second half of 2016.

The slowdown has to be related to something else, too, not just the Sports Authority liquidation. After all, that outlet was only 3% of revenue. In order to jump-start growth, Under Amour announced a plan to begin selling its merchandise in over 600 Kohl's (KSS) locations beginning in 2017. And the company is making a big push overseas. But I'm afraid the turn won't come fast enough.

Fiscal 2014 booked 32% growth, and now the company is looking at 22% to 24% growth for fiscal 2017. It's hard to pay 48 times 2017 estimates (of 78 cents per share) for a company whose growth has slowed so dramatically.

It's going to be tough for Under Armour to get back in the game.

This article is commentary by an independent contributor. At the time of publication, the author held no positions in the stocks mentioned.

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