Chavez has been battling an injured left knee since Spring Training and he has been on the DL since June 8.
"It's kind of a degenerative issue," D-backs manager Kirk Gibson said. "He's had extensive treatment on that, an aggressive treatment on that knee all year and it just doesn't respond now. Whereas before the time off it responded, which tells you it's degenerating more and more."
Chavez does not want to push things right now, because at age 36, he knows he is nearing the end of his career.
"I'm just so close to the end, you know, where I've got to worry about feeling good for the rest of my life," Chavez said. "So surgery would be the worst-case scenario for me to kind of be going down that line."
Chavez was asked if he planned on retiring at the end of this year.
"It's a possibility," he said. "I'm never going to say never. For some reason I have this personal rule that when guys retire you've got to be away from the game for two years before you officially say you retired. Because there's too many that come back."
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.