PHOENIX -- When Cubs starting pitcher Paul Maholm smacked a two-run homer in the fourth inning on Saturday to give his club a lead, he simultaneously drove in more runs than the Cubs' offense had in its previous two games combined.
It was the type of hit that could have jump-started and energized a beleaguered team to break out of a slump.
But for the second consecutive night, the Cubs stranded double-digit runners on base and failed to keep the D-backs offense at bay as they dropped their third straight game, 10-5, at Chase Field.
"We got some hits, scored some runs, but we left some people out there in key spots," Cubs manager Dale Sveum said. "Couldn't get that big hit, the scoring-position stuff is getting bad."
The Cubs had 14 hits, but left 10 on base and were 2-for-11 with runners in scoring position. They also collected nine hits and left 11 stranded on Friday.
David DeJesus and Starlin Castro each tied career highs with four hits on Saturday as the leadoff and two-hole hitters in the lineup. But Bryan LaHair, who batted third, went 0-for-5 and grounded into a double play.
"He had a tough night, he left a lot of people out there," Sveum said of LaHair. "Have to get better with men in scoring position. He's struggled all year and it's continuing, you have to change the approach or whatever. He's got to get better at that."
Maholm hit the second home run of his career on a no-doubter to left field off D-backs starter Ian Kennedy, but was touched up for seven runs (six earned) on nine hits over 3 1/3 innings. His other homer came May 9, 2009, against the Mets. The last Cubs pitcher to hit one was Carlos Zambrano last August.
"I hit a home run on the first pitch, jogged around the bases and came in," Maholm said when asked if the at-bat affected his pitching. "I would rather go 0-for-4 with four punchouts and get deeper into the game and win."
The half-inning after Maholm hit his homer he allowed six runs to the D-backs, aided by a Luis Valbuena throwing error at third base that Maholm thought could have turned into a double play to end the inning.
"You make a pitch and think you're getting out and then all hell broke loose," Maholm said. "I didn't make any pitches after it, and obviously it was a grind."
The Cubs starter also walked Kennedy twice, including once when the pitcher was squaring around to bunt.
"It's frustrating, that's a word you can print," Maholm said. "Obviously, in a bunt situation, I was trying to get him to hit the ball back to me hard and get a double play ball, but I just didn't throw strikes."
The outing was Maholm's shortest since August 30, 2010, when he also lasted 3 1/3 innings, giving up eight runs to the Cubs as a Pirates pitcher.
The D-backs broke the scoreless tie in their half of the third inning on a leadoff homer by Justin Upton. The right fielder picked on a full-count fastball from Maholm and drove it into the left-field bleachers.
"We capitalized on mistakes," Upton said. "That's what you have to do if you want to score runs."
Maholm briefly put the Cubs ahead, 2-1, in the fourth with his home run, but the 29-year-old allowed seven of the first eight batters in the bottom of the inning to reach base before Sveum brought in Jairo Asencio from the bullpen.
"He didn't have a whole lot after the home run he hit," Sveum said. "That seems to be our Achilles heel, when one of our pitchers gets a hit or does something good like that, the next inning ain't too good."
The Cubs cut into the deficit in the fifth with a two-run double from Steve Clevenger and a pinch-hit RBI single from Jeff Baker to make it 7-5, but Paul Goldschmidt countered with a solo shot in the sixth to put the D-backs ahead, 8-5.
Aaron Hill and Miguel Montero each followed with RBI singles to cap the 30-hit night between the clubs.
Tyler Emerick is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.