Nike (NKE) - Get Report is set to report quarterly earnings on Tuesday after the markets close. Analysts expect the sportswear company to post earnings of $0.56 a share on sales of $8.88 billion. During the same quarter a year ago, the company posted profits of $0.67 a share with revenue of $8.41 billion. If it pans out, the 16% year-over-year drop in quarterly earnings would be its first decline since 2012. Analysts will be watching the company's basketball unit amid increasing competition from Under Armour (UA) - Get Report . TheStreet's Scott Gamm reports from Wall Street.