D-backs manager Kirk Gibson said Hudson will throw an inning of relief either Tuesday or Wednesday against the Padres in San Diego.
Hudson was a starter for the D-backs before suffering a torn ulnar collateral ligament on June 26, 2012, in Atlanta.
Just days away from being activated last June, Hudson suffered another tear of the ligament and was forced to undergo a second Tommy John procedure. Given the two surgeries, Hudson's future -- at least in the near future -- is likely as a reliever.
"He's throwing the ball good," Gibson said. "Everything has gone smooth, progressing along nicely. Feels good, pretty good location, has had good life on his fastball."
Hudson has been clocked up to 95 mph during his rehab outings. The team will limit him to 25-to-30 pitches in his outings during September and make sure that he has plenty of time to get warmed up.
They've talked about getting him as many as six appearances during the month, but that has not been decided yet.
"I don't know that we have that figured out," Gibson said. "We'll just watch it and play it by ear."
Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.