James McDonald dealt six shutout innings to lead the Pirates to a 2-1 win over the Cardinals.  McDonald improved to 11-and-5 on the season.  Pittsburgh scored both its runs in the fourth inning on a passed ball and a wild pitch.  Joel Hanrahan locked down his 34th save in the Pirates' second straight win.  Tony Cruz plated the only run for the Cards on a ground out.  Jake Westbrook was tagged with the loss as St. Louis has dropped two-in-a-row.