Hampton allowed one hit and struck out two in three innings at the Braves' complex in Lake Buena Vista, Fla. He threw 30 pitches and reported no discomfort afterward.
"I'm very pleased," Braves general manager Frank Wren said. "He's happy and there was no pain. He feels very good going through this process."
The 35-year-old left-hander strained his left pectoral muscle while warming up in the bullpen for his season debut on April 3 against the Pirates. He was placed on the DL after the game.
During what was supposed to be his second and final Minor League rehab start on April 30, Hampton had to be removed in the fourth inning when he tweaked the muscle.
Hampton said two weeks ago that he hoped to be back sometime around the All-Star break in mid-July, which now seems plausible.
Everyone in the Braves organization has learned to be cautiously optimistic when it comes to Hampton, who hasn't pitched for the Braves since Aug. 19, 2005, due to a variety of injuries.
Over the past month, Hampton has progressed from playing catch at varying distances to throwing off a mound. He threw 50 pitches in a simulated game on Tuesday at the Braves' complex.
Ryan Lavner is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.