Major League Baseball maintained its racial and gender hiring practices in the last year, while the percentage of African-American players equaled a study's all-time low set in the 2007 season.Pittsburgh Pirates relief pitcher Mark Melancon (35) is greeted by catcher Chris Stewart after getting the last out in the ninth inning of the baseball game against the San Francisco Giants on Wednesday, May 7, 2014, in Pittsburgh. The Pirates won 4-3.Pittsburgh Pirates' Andrew McCutchen, right, is greeted by teammates after scoring in the first inning of the baseball game against the San Francisco Giants on Wednesday, May 7, 2014, in Pittsburgh.