Shares of Under Armour (UAA) - Get Under Armour, Inc. Class A Report were sinking over 4% during afternoon trading on Thursday following a cautionary note from Susquehanna.

Susquehanna analyst Sam Poser argues that while sales of the company's recently released Curry 4 basketball shoes have been good, they are "not good enough."

Poser contends that "incremental sales" at Kohl's (KSS) - Get Kohl's Corporation (KSS) Report , DSW (DSW) - Get Designer Brands Inc. Class A Report and Famous Footwear are not robust enough to offset the lost sales from the likes of Sports Authority, as larger retailers like Dick's (DKS) - Get Dick's Sporting Goods, Inc. Report plan down Under Armour products because of poor product segmentation.

"SportScanInfo (SSI) data indicates that ~34% of the UAA apparel styles carried in the moderate channel made up ~84% of the sales mid-March through May," he noted. "We recognize the aforementioned ratio is not unusual. However, the 34% of the styles that make up 84% of the business are carried in the athletic channel (Not Segmented)."

Retailers will begin to planning down their Under Armour business because they "do not want to get caught in a promotional free-for-all which is likely to occur when retailers such as Kohl's start discounting," he added.

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