Kelly, who had reconstructive surgery on his right elbow on April 2, threw 35 pitches at 50 percent and another 30 pitches at 70 percent, all under the watchful eyes of the training staff as well as new upper level pitching coordinator, Trevor Hoffman.
"We're just starting getting built up to get into games," Kelly said. "This is the next step in our program."
Earlier this week, Padres manager Bud Black estimated that Kelly is "three or four weeks" behind the other pitchers here in camp. Kelly himself said recently that he hopes to be pitching in real games by April or May, even if they are Minor League rehabilitation games.
For now, though, he's content with the path he's on. This was Kelly's second bullpen session since he arrived in Arizona last week, but the first where he's thrown more than 50 pitches.
"That [three or four weeks behind the other pitchers] is a pretty good assessment of where I'm at," he said. "That's what I'm setting my goal at. And if we have to take a day off, we can."
Corey Brock is a reporter for MLB.com. Keep track of @FollowThePadres on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.