Under Armour is a big loser today, falling roughly 6 percent, after UBS cut its rating on the stock to "neutral" from "buy" while keeping a $105 price target.
The athletic clothing and footwear maker's downgrade comes after a 50 percent surge this year for the stock, taking it as high as $107.86.
UBS analyst Michael Binetti told CNBC's " Fast Money Halftime Report " he made the call "mostly on valuation ... making it harder to put fresh money at work here."
He also noted warm weather in March and April probably pulled sales forward in the quarter and have been slowing recently.
In addition, competitor Nike has reversed some of the price hikes that had helped Under Armour increase its market share.
In a live interview on " Closing Bell " Wednesday, CEO and Founder Kevin Plank was confident Under Armour will continue to grow in coming years, with footwear eventually becoming a bigger seller for the company than apparel.