Brandon Belt, Buster Posey and Michael Morse hit home runs, each to lead off an inning, and the streaking San Francisco Giants beat the slumping Atlanta Braves 3-1 on Saturday night in a matchup of first-place teams.Atlanta Braves' Justin Upton (8) comes up safe at second base after San Francisco Giants shortstop Brandon Crawford could not handle the throw after Evan Gattis reached on a force attempt during the second inning of a baseball game, Saturday, May 3, 2014, in Atlanta.San Francisco Giants' Buster Posey (28) connects in the sixth inning after hitting a home run in the fourth inning to go ahead against the Atlanta Braves in a baseball game, Saturday, May 3, 2014, in Atlanta.Members of the Negro League baseball teams from years past are honored before the start of a baseball game pitting the San Francisco Giants against the Atlanta Braves, Saturday, May 3, 2014, in Atlanta.San Francisco Giants pitcher Ryan Vogelsong works the mound against the Atlanta Braves during the first inning of a baseball game, Saturday, May 3, 2014, in Atlanta.