Trader Radar - Friday Jan. 18th

Q: On Fast Money’s trader radar we look at the stock that was lighting up screens across Wall Street. After hitching a ride on the growth of the NFL, this sports apparel maker was sacked for a loss this year. Known for its shirts that wick away perspiration, this Portland-based company just purchased a 60 second spot in the upcoming Super Bowl. But it's that ad for a new sneaker that has investors sweating about out of control marketing costs. Who is it?

A: Under Armour is on our trader radar. The stock was down about 20% Friday on more than 6 times the normal trading volume.