Is Under Armour Ready to Take Nike Head On?

Baltimore, Maryland — The message from Under Armour has gone from "Will you protect this house?" to "I Will".

The company is beginning 2013 with a new marketing campaign, and a renewed effort to make headway in sales beyond apparel for men, namely shoes and women. Both have been weaker segments for UA but are seen as huge growth opportunities.

Perhaps to investors, the shift in motto describes the next phase in the company's development: From disruptive growth company to global retail machine ready to take Nike head on.

A new 8,000 square foot store in Baltimore is part of this new push in the new year. Under Armour does have other stores, but they are mainly stores-within-stores, including Dick's Sporting Goods, Macy's or in malls.

(Read More: Nike and the NFL: Sizing Up Year No. 1)

The stand-alone store right in the company's backyard will serve as a test lab of sorts as the company tries to expand its direct-to-consumer sales.

Under Armour is at a critical stage right now. It's been public for more than seven years, and continues to grow revenue at the pace of 20 percent per quarter.

But it is still very much an apparel company, which makes up 75 percent of revenues — a much higher percentage than rival Nike, which derives billions from its footwear division.

(Read More: Swoosh! Inside Nike)

Under Armour's shoe business accounts for less that 15 percent of revenue.

In this new Baltimore store, which opens to the public on Saturday, shoes are everywhere, and it's a selection not found anywhere in the world.

Less than 10 percent of UA revenue comes from outside North America. Believe it or not, the Baltimore store could be part of that strategy as well. If it produces solid sales with it's stand-alone non-mall presence, it could be the template for moving outside US borders.

But even with all of the challenges facing the company as it tries to move beyond its early stage growth — and the stock's under-performance during the recent rally — sales have still doubled since 2010.

Those are difficult numbers to criticize.

—By CNBC's Brian Shactman; Follow him on Twitter: @bshactman