At the same time, neither side is ruling out a reunion or coming back together at some point.
The Giants declined to exercise Vogelsong's $6.5 million contract option for 2014 on Monday, but the parties agreed to keep open the possibility of potential negotiations down the road about a deal.
"The door's open for dicussions with Vogelsong, but we're not actively talking right now," assistant general manager Bobby Evans said Monday night. "Both sides are going to do some exploration of the market before we dive into that. I think it was somewhat the complexity of our overall needs going into the market ... to explore those fully, we need more time, and unfortunately we had to make a decision today."
Vogelsong went 4-6 with a 5.73 ERA in 19 starts and 103 2-3 innings during an injury-shortened season. He broke two bones in the right pinkie area of his pitching hand and also dislocated a knuckle on a swing May 20 and underwent surgery the next day. He had five pins inserted in his hand during the procedure at Stanford, performed by orthopedist Dr. Tim McAdams.
Vogelsong won 13 and 14 games, respectively, the previous two seasons. He is due a $300,000 buyout.
Evans said the Giants didn't offer Vogelsong a contract with a lower guaranteed salary.
"We did not put anything on the table. There's no formal process where we go from here," Evans said. "I think Ryan has always had interest in being a Giant, but he has the opportunity to explore other options. Today doesn't eliminate his chances of coming back."
San Francisco has been in discussions with lefty reliever Javier Lopez, and Evans expects him to explore his options in free agency.
"There's an open mind about what could happen and we're going to maintain contact," Evans said.
The Giants already declined their 2014 options on Saturday for $126 million left-hander Barry Zito -- $18 million with a $7 million buyout -- and outfielder Andres Torres for $3 million with a $500,000 buyout.
"These are three mainstays of our rotation, not only for the immediate past but going forward," Evans said. "This is the core of a solid rotation and we want to explore options on the market to make it better."
In addition Monday, Evans said Giants 17-year-old outfielder Gustavo Cabrera -- a top prospect in the organization from last year's international free-agent class -- flew to San Francisco for emergency surgery after an injury in his Dominican Republic home. The way Evans understands it, upon returning home from instructional league Cabrera slipped and tried to break his fall by raising his right arm but it went through glass and he nearly severed his wrist. The Giants' top team of doctors worked on Cabrera, who is now able to move his fingers again.
"How he flew to San Francisco in immense pain, I'll never know, a brave young man," Evans said. "He's 17 years old. I don't think it's career-threatening. We could be looking at a year or more of rehab to get him back to baseball activity."
A right-handed hitter Cabrera batted .247 with two home runs, seven doubles, four triples and 22 RBIs with 21 stolen bases in 54 games for the Giants' Dominican Summer League team this year.