Glavine allowed three runs and five hits against Toledo. He has been on the disabled list since the start of the season following elbow and shoulder surgery last August.
"I felt really good," said Glavine, who threw 56 pitches against the Mud Hens. "That is certainly as good of stuff velocity-wise on my fastball as I've had. The flip side was that I couldn't throw the ball where I wanted to. But I'll take that. I'd rather feel that my stuff was good and be fighting my location."
Glavine is scheduled to make a second rehab start for Gwinnett on Thursday, then likely get another in with Class A Rome before possibly rejoining the Atlanta rotation in early June.
Glavine made only 13 starts last season, going 2-4 with a 5.54 ERA, and went on the disabled list for the first time. He has a career record of 305-203 with a 3.54 ERA.
After he stopped a minor league rehab start April 12, the two-time NL Cy Young Award winner was diagnosed two days later with inflammation in his left rotator cuff.