Updated from 2:00 p.m. with closing price

It was a terrible Tuesday for Under Armour (UA) - Get Report .

Shares ofthe athletic-wear makercrashed 23.4% to $19.22 after it reported fourth-quarter results that fell short of analysts' expectations and issued disappointing full-year guidance. 

Before the opening bell, the Baltimore-based company posted adjusted earnings of 23 cents a share, below analysts' projections of 25 cents a share. Revenue came in at $1.3 billion, while analysts had forecast $1.4 billion.

"Numerous challenges and disruptions in North American retail tempered our fourth quarter results," CEO Kevin Plank said in a statement, who was likely referring to ongoing department store closures headlined by Macy's (M) - Get Report and sporting goods bankruptcies last year led by The Sports Authority

"Performance is certainly not dead," Plank told analysts on a conference call when asked about his company's core business of selling performance apparel. "We need to become more fashionable with the product that's out there," Plank added. 

Under Armour has been very vocal about its aspirations to continue to grow 20% annually, setting a goal of $7.5 billion in annual revenue by 2018. However, overall sales grew just 12% in the fourth quarter, the weakest it has increased in eight years.

Additionally, Chief Financial Officer Chip Molloy has decided to leave the company for personal reasons. Effective Feb. 3 David Bergman, senior VP of corporate finance, will serve as acting CFO. Molloy will remain with the company in an advisory capacity to assist with the transition.

For 2017, net revenues are expected to rise 11% to 12% to nearly $5.4 billion. Analysts were looking for full-year revenue of $6.1 billion.

"Tempered top line results coupled with strategic investments in the company's fastest growing businesses are expected to cause a decline in operating income to approximately $320 million," the company said.

For Under Armour, its more tempered outlook shouldn't come as a surprise based on comments by Plank in October that spooked Wall Street. 

What Do Under Armour CEO Kevin Plank's Recent Stock Sales Say About His Company?

Moving up in weight class for Under Armour to better compete with Nike  (NKE) - Get Report will require several big-time investments over the next two years that stand to take a bite out of profit. The investments arrive at a time in which the company's apparel sales are slowing after years of torrid growth, brick-and-mortar retailers are shuttering stores in droves thanks to the shift toward online shopping, and Adidas (ADDYY) and Reebok (owned by Adidas) have re-emerged on the cool club scene among shoppers.

One area of investment for Under Armour, and arguably its most important, will be on the sports marketing front. Nike pioneered the use of athletes and deals with sports teams to help hawk clothing and shoes, and now Under Armour will have to disrupt the standard bearer by opening up its checkbook.

Elsewhere, the upheaval in retail has placed extra importance on Under Armour establishing a more formidable store network of its own. Under Armour has over 160 company-owned stores in North America, made up mostly of outlets and several flagship stores in major urban markets. Nike has hundreds more stores in North America, and in total operates more than 900 retail locations globally.

Under Armour also will need product for its growing list of athletes to wear and for its new retail stores to carry to compete with Nike, Adidas and Reebok. Developing that will require investment in people, processes and infrastructure. In particular, expanding footwear -- which Under Armour sees growing to $1.7 billion in annual sales by 2018 from $678 million in 2015 -- is receiving extra attention from Plank and his team.

To aid this product development, Under Armour is expected to open a high-profile new Portland office (near Nike's HQ) in the spring or summer of this year.