Trevor Bauer's first taste of Major League Baseball has not been as sweet as expected.
Chase Headley smoked a three-run double and the Padres scored seven off the rookie en route to a 9-5 win in the second portion of a three-game set.
Yonder Alonso picked up two hits including a two-run home run for the Padres, who have won a season-high four in a row.
Andrew Cashner, who made his third start of the year for the Padres, left the game before the third inning with a strained right lat muscle. He threw two scoreless innings before showing discomfort warming up for the third inning.
The 21-year-old Bauer (0-1), one of the Diamondbacks' top prospects and the third overall pick in the 2011 draft, allowed seven runs -- six earned -- on six hits and four walks in 3 1/3 innings. He gave up two runs on five hits and three walks in four innings before leaving his first start at Atlanta June 28 with a strained groin.
"He didn't make good pitches," Arizona manager Kirk Gibson said of Bauer. "We know he has great stuff but we are going to try and refine some things so he can have more success the next time out."
"We strung together some at-bats," Padres manager Bud Black said. "We made him work today, he had a tremendous first inning, but after that I thought we started seeing the ball a little better. It looked as if his control was a little bit spotty, but that's not unexpected for a young guy making his first home start, but I thought overall we saw the ball better the second time through the lineup, you saw the results."
Jason Kubel hit a grand slam and Paul Goldschmidt went 4-for-5 with an RBI for the Diamondbacks, who have lost four straight.
After Yasmani Grandal stroked a one-out single in the second, Alonso jumped on a first-pitch fastball and crushed it over the right-field fence.
The Padres exploded for five more in the fourth. Cameron Maybin and Everth Cabrera delivered back-to-back one-out singles to put runners on the corners. Ross Ohlendorf laid down a safety squeeze bunt, which Bauer mishandled, allowing Maybin to score and Ohlendorf to reach first. After Will Venable walked and Alexi Amarista singled to drive in a run, Headley cleared the bases with a double to center, ending Bauer's night and giving the Padres a seven- run cushion.
Maybin knocked in Alonso, who led off the fifth with a double, to push the lead to eight.
Arizona cut the Padres' lead in half in the bottom half of the fifth. Patrick Corbin walked and Stephen Drew and Aaron Hill followed with singles to load the bases. Two batters later, Kubel blasted his eight career grand slam, a shot to right.
The Padres got a run back when Jesus Guzman hit his second pinch-hit home run of the year in the eighth inning.
After Nick Vincent, Dale Thayer and Joe Thatcher threw scoreless innings in the sixth, seventh and eighth, Luke Gregerson wrapped up the win after allowing a two-out RBI hit by Goldschmidt.
Ohlendorf (2-0) got the win after allowing three runs in 2 1/3 innings in relief of Cashner.
San Diego won its first series at Chase Field since taking two of three from May 25-27, 2009...Armarista, who went 2-for-5 with an RBI and a run scored, has gone 11-for-21 in his last six games...Headley has an eight-game hit streak and Amarista's reached seven games...Arizona has hit a home run in 14 straight games, a single-season club record...Hill, who went 2-for-5, has hit safely in 18 straight games at Chase Field, the fourth-longest streak in club history...Arizona went 3-for-14 with runners in scoring position and left 10 on base...Kubel's last grand slam was on July 25, 2010 with the Minnesota Twins in Baltimore.