Ryan Dempster struck out a season-high 11 and snapped a six-game Wrigley Field losing streak to help the Chicago Cubs beat the San Francisco Giants 11-4 Friday. Dempster (2-4) allowed two runs and six hits in six innings and the Cubs ended San Francisco's six-game winning streak. Reed Johnson went 3 for 5 and drove in four runs, three on a bases-loaded triple in the seventh.