David Ortiz continued his power surge with a grand slam and Dustin Pedroia extended his career-best hitting streak to 24 games, all part of Boston’s 12-5 rout of the Kansas City Royals. Ortiz, who had four hits and five RBI in Tuesday’s 13-9 triumph, went deep off Bruce Chen on Wednesday. The fourth inning homer gave him 1,000 RBI in a Red Sox uniform. Pedroia, who went 3-for-4 with a pair of RBI, stretched his hitting streak by smacking a homer off Chen in the first inning. Adrian Gonzalez drove in three runs for the AL East leaders, who are 18-4 this month.