"He's still ahead of schedule," Hurdle said. "He could be ready by September 1 [a logical target date, since rosters expand from the 25-man limit that day]. He's got to build up only to one inning."
Left-hander Wandy Rodriguez, absent for nine weeks also with a forearm injury, could throw his first bullpen at Coors Field, putting him even ahead of Grilli's schedule. However, as a starting pitcher, Rodriguez has to stretch out his arm more and thus is not a Sept. 1 option.
James McDonald, out since early May with shoulder discomfort, is set to launch into his own throwing agenda, at the team's Pirate City complex in Florida. McDonald's program calls for him to work up to 50 pitches, making him only an outside possibility for late-season long-relief help.
"Wandy won't be a Sept. 1 add," Hurdle said. "The progression he has to go through, to build up to at least five innings and 80 pitches, will take us past that date."
Since they are on the DL, Grilli and Rodriguez would both be eligible for the postseason, even if not on the active roster at the normal cutoff date of Aug. 31.
"If we get Wandy and Grilli back, it'll be nice. But we know we're capable right now with what we have," said Hurdle, who admitted he would like to have a third lefty for his stretch and playoff rotation. "Whether I get it or not, I don't know. Like I'm always telling my daughter, 'Get what you can get, and don't throw a fit.'"
Tom Singer is a reporter for MLB.com and writes an MLBlog Change for a Nickel. He can also be found on Twitter @Tom_Singer. This story was not subject to the approval of Major League Baseball or its clubs.