Drew (ankle) played three innings of an extended spring game on Friday, Hudson (shoulder) played catch from 60 feet the same day and Young (shoulder) continues to receive treatment.
"I wish I had a crystal ball to know exactly when C.Y. and [Hudson] will be back," D-backs general manager Kevin Towers said. "It would really help us for planning purposes, but until he really gets up and starts letting it go, we won't really know.
Drew's 2011 season ended in July, when he suffered a devastating right ankle injury. Towers said he plans on going out to watch Drew when the team returns home next Monday following this 10-game road trip.
"He's feeling better and better, less stiff in between times that he plays," Towers said. "He's getting close. It will be nice to see where he's at when we get back home."
Overall, Towers said he has been happy with the way his 10-10 team has played so far this year.
"They've been a resilient bunch," Towers said. "We've played great defense, which has really been good other than that game we made five errors. We've defended very, very well. For the most part, our bullpen has been good. We haven't blown many games late."