SAN DIEGO -- Jason Hammel, who has been sidelined with a right arm injury, experienced a setback while throwing on Tuesday.
"It was a slight improvement, but it was disappointing that it didn't heal after a week of not throwing," said Hammel, who will try to throw again on Friday. "I can't predict the future, but as of right now, it doesn't look too good" to come off the disabled list when he is eligible.
The right-hander was placed on the disabled on July 31 (retroactive to July 29).
"Still had a little discomfort, so we are not there yet where he's in throw mode," manager Buck Showalter said. "[Aug. 13] is his eligibility [date], today is the 7th. If you go through the throwing and what have you, he will probably pitch in a [rehab] game, maybe. I don't think that's moving at a real fast clip. We were hoping yesterday he would throw and want to go to the next step.
"It's not bad, but it's not completely gone. Some of it is still lingering. Makes me a feel a little better about DL'ing him in the first place, because I was kind of iffy."
The 30-year-old Hammel is 7-8 with a 5.20 ERA in 21 starts and has been dealing with what is being called right flexor mass tightness since Spring Training, with the team opting to place him on the DL when they acquired starter Bud Norris at the Trade Deadline.
Showalter said part of Hammel's rehab is taking medication to reduce the inflammation, and he could start feeling better over the next couple days.
Brittany Ghiroli is a reporter for MLB.com. Read her blog, Britt's Bird Watch, and follow her on Twitter @britt_ghiroli. This story was not subject to the approval of Major League Baseball or its clubs.