Shares of Nike Inc NKE.N rose more than 4% in after-hours trading after the company beat quarterly revenue estimates. By Stephen Culp NEW YORK, March 21 (Reuters) - Wall Street closed lower on Monday, with stocks extending their slide after U.S. Federal Reserve Chairman Jerome Powell hinted at a more aggressive tightening of monetary policy than previously anticipated, adding to uncertainties regarding the Russian invasion of Ukraine. The central bank must move "expeditiously" to combat inflation, Powell told the National Association for Business Economics conference, adding that bigger-than-usual interest rate hikes could be deployed if needed.