Jackson allowed three hits, walked one and struck out six.
Joe Blanton pitched 5 1-3 innings for Los Angeles and was charged with three runs and four hits. The veteran right-hander has pitched well since moving from the first-base side of the pitching rubber to the third-base side before his last spring start.
Chicago scored three times with two out in the third. Emilio Bonifacio drove in McDonald with a triple, and then scored on Ryan Roberts' double. Anthony Rizzo singled in Roberts.