Diamondbacks 8, Astros 1: Ian Kennedy pitched six solid innings and Aaron Hill homered twice as visiting Arizona completed a three-game sweep and handed interim Houston manager Tony DeFrancesco a loss in his debut.

Chris Young added an RBI single and Gerardo Parra doubled in a run during a five-run fourth inning for the Diamondbacks, who have won four straight to pull three games over .500 (62-59) and remain in the playoff race in the National League West.

The Astros fired manager Brad Mills on Saturday night and announced DeFrancesco as the interim replacement on Sunday morning. Houston has lost four straight and is 6-30 since the All-Star break.

Armando Galarraga (0-4) held Arizona to one hit through the first three innings but fell apart in the fourth. Hill led off the frame with a solo home run and Jason Kubel and Paul Goldschmidt followed with singles before the first out. Young’s single made it 2-0 and a pair of walks forced in another run before Kennedy lifted a sacrifice fly and Parra doubled to deep center, ending Galarraga’s afternoon.

Kennedy (11-10) did not have his best stuff but managed to work around five hits and five walks. The right-hander struck out seven and allowed one run to snap a two-start losing streak.

Houston thought it had gotten on the board with a solo home run in the bottom of the fourth, but Fernando Martinez’s long drive was ruled a double after a replay review. He was stranded at third.

The Astros finally pushed a run across in the sixth but Miguel Montero singled in two runs in the seventh and Hill’s second solo homer - his 17th - in the eighth turned it into a rout.

GAME NOTEBOOK: Astros general manager Jeff Luhnow said that the team will search immediately for a permanent manager, with DeFrancesco among the candidates to fill the position long term. DeFrancesco had been managing Houston’s Triple-A team in Oklahoma City. Ty Van Burkleo was named interim hitting coach and Dan Radison will take over first-base coaching duties on an interim basis. … Kubel (stiff neck) returned to the starting lineup after a two-game absence. … Hill went 7-for-12 with three home runs, five RBIs and six runs scored in the series.