Nike has also lost basketball sales after Under Armour poached the NBA's Golden State Warriors star Stephen Curry in 2013.
"[Many] factors have shifted consumer patterns ... in North America, impacting traffic, the economics of brick-and-mortar retail, and it's driving a more promotional environment in the near term," Chief Executive Mark Parker said in a conference call after the report.
But Cramer said he believes Nike is coming back, and said the sportswear company is not a fan of Under Armour CEO Kevin Plank.
"They've got the balance sheet. They've got the technology. And they do not like Kevin Plank," Cramer said on "Halftime Report." "They are saying, 'We are going to eviscerate you, Plank.'"
Shares of Under Amour dropped on Monday after FBR Capital Markets lowered its rating on the stock to "underperform" from "market perform." The investment firm said the decision was due in part to an "intensifying" price war between Nike and Under Armour.
Nike shares are up 9 percent year to date as the company continues to battle the North America retail landscape.
— Reuters and CNBC's Lauren Thomas contributed to this report.