Jeff Samardzija pitched seven strong innings to get the win. He allowed just one run and four hits while striking out 11. The 11 strikeouts tie Samardzija's career high set last month against the Braves.
The Cubs offense gave Samardzija plenty of early run support, including two runs in the second inning on a Darwin Barney two-run home run. Chicago added another run in the third inning before a two-run Alfonso Soriano home run in the fifth inning made it 4-0.
The lone bright spot for the Astros was a pinch-hit solo homer by Brandon Barnes. It was Barnes' first Major League home run after being called up from Triple-A last week.
The two teams will meet in game two of the series Tuesday night at 8:05 p.m. ET.
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