BOSTON — Red Sox manager Alex Cora , who rode a roster with Mookie Betts, Xander Bogaerts, Rafael Devers and Chris Sale to the most successful season in franchise history and then struggled to win with the discount lineups that replaced them, was fired on Saturday with Boston again mired in last place in the AL East. Cora, who was an infielder on the Red Sox 2007 World Series championship team and managed them to a franchise-record 108 wins and another title in '18, will be replaced on an