PITTSBURGH (AP) -- Andrew McCutchen made a ''minor'' adjustment in the batter's box a couple weeks ago hoping to give him a fraction of a second longer to see what's coming.
Consider the experiment a success.
''When I get the barrel to it, good things happen,'' McCutchen said. ''That's basically what I'm doing.''
McCutchen drove a two-run shot to right field in the third inning then added an RBI-double in the fifth off Edwin Jackson (4-6) as the Pirates bounced back from two tough losses to Milwaukee over the weekend in which they left a combined 18 runners on base.
There were no such problems while sending Jackson to his fourth loss in his last five decisions.
''I got to do a better job of mixing up instead of getting beat with same pitch twice,'' Jackson said. ''I let the guy who's the threat on the team beat me twice and you can't do that.''
Charlie Morton (3-7) allowed one run over seven innings to win for the third time in his last four starts after beginning the season 0-6. Ike Davis hit his fifth homer of the season while Starling Marte broke out of a lengthy slump with three hits.
Starlin Castro went 3 for 4 with his eighth home run and two RBIs for the Cubs, who fell to 10-22 on the road, the worst mark in all of baseball.
''We try to figure out what it is but we haven't figured it out yet,'' Castro said. ''You go back and see those games we play good at home and we should be playing that way on the road but we're not.''
It wasn't exactly the best way to start a 10-game road swing for Chicago, which was coming off a successful 5-1 homestand that included the team's longest winning streak in more than a year.
Any momentum generated at Wrigley Field vanished on a night Morton avoided the control problems that have plagued him much of the season. The right-hander came in with a major-league high 13 hit batters while averaging nearly 2.5 walks per start.
Maybe it was the extra day of rest he asked for after feeling tired following a win over San Diego last week, but Morton's wildness vanished for seven innings at least. He didn't walk a batter, struck out a season-high seven and needed just 82 pitches to get 21 outs.
''I don't think it was great control but I got some quick outs, that helps,'' Morton said. ''Not so many deep counts. Not as erratic, my misses were more in the zone and I got away with them.''
The Cubs needed a grounder deflecting off the glove of shortstop Jordy Mercer to extend the sixth inning before finally scoring on Castro's long double to right.
All the run did was draw Chicago within 4-1, with most of the damage done by the reigning NL MVP.
Marte, who began the night 0 for his last 23, doubled home Pedro Alvarez to give the Pirates the lead in the first. McCutchen pushed it to 3-0 in the third when he patiently waited as Jackson worked him away before reaching out and sending a pitch into the first row of seats in right for his fourth homer this month.
McCutchen nearly did it again two innings later, lacing a double off the wall in right to score Travis Snider and give Morton all the cushion he would need. Bothered by some bad luck early in the season, Morton lowered his ERA to 3.14.
NOTES: Pittsburgh 2B Neil Walker was scratched about an hour before the first pitch with abdominal pain and underwent an emergency appendectomy. The team placed Walker on the DL after the game and called up highly touted prospect OF Gregory Polanco from Triple-A Indianapolis. Polanco hit .347 with seven home runs in the minors this spring. ... Pirates RHP Gerrit Cole threw 25 soft-toss pitches on flat ground before the game. Cole, who leads the Pirates with six victories, was placed on the DL on Sunday with what the team is calling right shoulder fatigue. ... Chicago RF Ryan Sweeney made a rehab start for Class A Kane County on Monday night. Sweeney went on the DL May 3 with a right hamstring strain. ... The series continues Tuesday. Travis Wood (5-5, 5.04 ERA) starts for the Cubs against Francisco Liriano (1-6, 4.54). Wood is 2-4 with an 8.04 ERA on the road this season.
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