Ryan Howard had three hits, including a grand slam, and finished with six RBIs to lead the Philadelphia Phillies to a 12-2 rout of the Pittsburgh Pirates on Monday.

Howard had a two-run single in the third and his seventh homer of the season off reliever Jack Taschner in the eighth to cap the night’s scoring and the team’s 13-hit attack as the Phillies improved to 12-3 in May. The club is averaging more than six runs per game during the stretch.

Jason Werth added four RBIs, including a three-run homer off Pirates starter Charlie Morton. Jimmy Rollins, who had been out since April 13 with a calf strain, had two hits and scored two runs in his return to the lineup after coming off the disabled list.

Kyle Kendrick (2-1) scattered five hits and two runs over eight innings to gain the victory as the Phillies defeated the Pirates for the sixth straight time and 11 of the last 12 meetings in Philadelphia.

Delwyn Young drove in both runs for the Pirates, including a solo homer in the top of the first inning.

Morton (1-7) was tagged for six runs on six hits in four innings.