PHILADELPHIA — Kyle Kendrick pitched eight impressive innings, Ryan Howard hit a grand slam and had six RBIs, and the Philadelphia Phillies beat the Pittsburgh Pirates 12-2 on Monday night.

Jayson Werth had a three-run homer for the NL East-leading Phillies, who have won four straight and 12 of 15. The two-time defending NL champions are 24-13 despite a slew of injuries.

Pitching in a steady rain, Kendrick (2-1) allowed two runs and five hits, striking out four.

The Phillies got one of their injured stars back when Jimmy Rollins returned to the lineup after missing 29 games with a calf injury. The three-time All-Star shortstop and 2007 NL MVP had two hits and an RBI.

Pirates starter Charlie Morton (1-7) gave up six runs and six hits in four innings. Delwyn Young hit his first career leadoff homer for Pittsburgh, which has lost six of eight. The Pirates have dropped six in a row and 11 of 12 in Philadelphia.

Kendrick had just his third quality start in eight outings, lowering his ERA to 5.24. The right-hander had a sharp sinker, and got 12 outs on grounders.

Young hit Kendrick's fourth pitch into the right-field seats for a 1-0 lead, but the Phillies manufactured a run in the bottom half. Shane Victorino singled leading off, stole second, advanced to third on a groundout and scored on Rollins' RBI groundout.

Howard's two-out, two-run single in the third put the Phillies ahead 3-1 after Rollins popped out with the bases loaded. Howard beat the shift with a hard grounder through the vacated shortstop hole.

Werth followed with an opposite-field shot to right to make it 6-1. He's hit three-run homers in three of the last five home games, dating to the previous homestand.

Werth added an RBI double in the seventh. He leads the majors with 20 two-baggers. Howard connected off Jack Taschner in the eighth. It was his ninth career slam, extending his franchise record.

NOTES: Rollins batted third instead of his usual leadoff spot because Chase Utley, the regular No. 3 hitter, was sent home with flulike symptoms. ... To make room on the roster for Rollins, infielder Wilson Valdez was designated for assignment. Valdez hit .231 (12 for 52) for the Phillies. He filled in nicely after backup shortstop Juan Castro got hurt. ... Pirates INF Aki Iwamura grounded out as a pinch hitter in the fifth. He's hitless in his last 27 at-bats. ... Phillies LHP J.A. Happ threw 20 pitches in a bullpen session. He's been sidelined with a left forearm strain. ... A crowd of 45,371 was the 59th straight sellout at Citizens Bank Park.