Recap: Los Angeles vs. Arizona

Los Angeles, CA (Sports Network) - Chris Johnson debuted with a bang, or rather, a slam, on Monday, as the Diamondbacks downed the Dodgers, 7-2, in the opener of a three-game series.

Johnson, who was acquired from the Astros on Sunday, became the first player to hit a grand slam in his Diamondbacks debut when he belted a 2-1 slider from Aaron Harang into the seats in left in the fifth inning.

"I got into town early this morning," said Johnson. "This is like opening day for me. My nerves were running wild."

Paul Goldschmidt added a three-run, first-inning blast for the Diamondbacks, who trail both the Dodgers and Giants by 3 1/2 games in the NL West.

Trevor Cahill (9-9) gave up one run on six hits over six innings to earn the win. He walked three and struck out four.

Matt Kemp finished with three hits, including an RBI double, while Hanley Ramirez went 0-for-4 in his home debut as a member of the Dodgers.

Harang (7-6) was charged with seven runs on nine hits over five innings in the loss.

"Aaron didn't seem like he had his good stuff," said Dodgers manager Don Mattingly.

Los Angeles, which was coming off a three-game sweep of the Giants, made a trade Monday night, acquiring right-handed reliever and 2011 All-Star Brandon League from the Mariners for a pair of prospects.

Goldschmidt hit his 14th homer of the season, plating Gerardo Parra and Aaron Hill, who opened the game with consecutive singles.

Johnson made it 7-0 with his second career grand slam, both of which have come this year. With Hill and Jason Kubel aboard, Harang intentionally walked Miguel Montero to get to the newly acquired third baseman.

"Any time they walk a guy in front of you, you want to get a big hit," continued Johnson.

In addition to his eighth-inning RBI double, Kemp crossed the plate in the sixth on Jerry Hairston's groundout.

"We had good energy we just couldn't get the big hits early to get back into the game," Mattingly said.