"Everything went very smoothly and very well," said Hahn of Jones, who did not retire any of the five batters he faced this season. "We'll re-evaluate in a month.
"After a month, it's conceivable we'll ramp up baseball activities and he can return soon thereafter as tolerated by the baseball activities. At that point, it's more about getting him into pitching shape than dealing with the back. We'll see in a month and come up with a timeframe then."
Scott Merkin is a reporter for MLB.com. Read his blog, Merk's Works, and follow him on Twitter @scottmerkin. This story was not subject to the approval of Major League Baseball or its clubs.