The Milwaukee Brewers saved the best for last, erupting for nine runs in the ninth inning to rout the Chicago Cubs at Wrigley Field Monday night 15-4.   The Brewers smashed five home runs and delivered 21 hits in the victory.  Aramis Ramirez hit a pair with four runs batted in, Corey Hart and Carlos Gomez hit solo shots and Ryan Braun launched a three run bomb to cap a four for six night with 5 runs batted in.  Marco Estrada got the win working five innings, allowing three unearned runs with eight strikeouts.  The game was actually close throughout, with Kameron Loe getting out of a bases loaded jam when Hart made a diving stop of a groundball.  Gomez, who also had four hits, launched his home run in the 8th for a 6-4 lead before the Brewers hammered the Cubs bullpen in the final at bat.  The Brewers (60-67) will send Yovani Gallardo against Travis Wood in game two of the series Tuesday night.