MIAMI — Kris Medlen allowed only an unearned run in seven innings Tuesday night, and the Atlanta Braves earned their fifth consecutive victory by beating the punchless Miami Marlins 3-2. The Braves improved to 7-1, their best start since 2007. The Marlins fell to 1-7 with their fourth consecutive defeat, and they're off to their worst start since the 1998 team began the season 1-11.