Parnell wasn't available for Friday night's opener, and his status for the weekend is unknown as he deals with a stiff neck.
''Bobby has seen the doctor,'' Mets manager Terry Collins said Friday. ''He has gotten some medication to quiet this area down, see if we can get those muscles to relax a little bit. He will be re-examined on Monday.
''He is not available tonight for sure, and probably tomorrow but maybe Sunday.''
David Aardsma is expected to handle closing duties.
''We're really lucky because we've got David Aardsma, who has closed in the past,'' Collins said. ''We'll probably use him right now - leave (LaTroy Hawkins) where he is. He has done such a great job in that eighth inning. I don't want to mess that up.''
Edgin will be lost for perhaps 4 to 6 weeks after a stress fracture in a left rib was revealed Friday in an MRI.
''There is no real timetable. They don't know how long,'' Edgin said. ''I have heard four weeks, I have heard six weeks. You don't know exactly how long it's going to take for a bone to heal.''
The left-hander was placed on the disabled list, and left-hander Pedro Feliciano was brought up from Triple-A Las Vegas and was available to pitch Friday night.
Edgin has been feeling discomfort on his left side for a while that got worse after his most recent appearance Monday at Miami. He felt pain most often after his outings once adrenaline had worn off.
''I had a little pull in my side and I was pitching well so I wanted to keep going,'' he said. ''It just progressed and got a little worse the other day.
''Until the other day it was fine. It wasn't even when I was feeling. It was when I was coming down off that adrenaline rush that I would feel it. This kind of caught me off-guard this morning.''
Edgin has been pitching well, allowing only two runs in 19 1-3 innings over 23 appearances since being recalled from Las Vegas on June 10. He has stranded 18 of 22 inherited runners, the eighth-best rate in the National League, and stranded 14 of the past 16.
He is expected to be evaluated soon, but that hasn't been scheduled yet.
''It is very frustrating,'' Edgin said of the injury. ''I was starting to get on a roll there, throw like I can throw, starting to figure out some things mechanically. It just happens I guess.''
The 36-year-old Feliciano hasn't pitched in the majors since 2010 with the Mets, when he worked in a franchise-record 92 games.
The left-hander was 0-0 with one save and a 1.29 ERA in 22 minor league games this year with Class A St. Lucie of the Florida State League, Double-A Binghamton of the Eastern League, and Las Vegas.
He allowed 14 hits, issued four walks and struck out 19.
Starting pitcher Jonathon Niese, who is out with an inflamed rotator cuff, is getting closer to a return to the Mets.
After pitching four scoreless innings for St. Lucie in a rehab outing on Thursday, Niese is expected to toss a bullpen session on Saturday at Citi Field.
If that goes well, the lefty will likely have another rehab outing either at Brooklyn or Binghamton soon.