The Giants have informed Ryan Vogelsong that the club won’t pick up his $6.5 million option, but sources say the two sides have begun discussions on a restructured contract.

The Giants are interested in bringing back Vogelsong, but for a smaller guaranteed salary with incentives based on innings and/or starts.

The club is expected to announce its intention with Vogelsong on Monday, and also make official the decision to decline options on Barry Zito and Andres Torres; both Zito and Torres were on a list of free agents that the Major League Players’ Association released on Saturday.

Vogelsong is a 2011 All-Star and a 2012 postseason hero whose late-career comeback ranks as one of the most inspiring tales in recent franchise history. But he’s also going to turn 37 in July and is coming off a difficult season in which he went 4-6 with a 5.73 ERA and 1.56 WHIP.

His struggles were acute even before May 20, when he was struck by a pitch that crushed the pinky finger on his pitching hand. He returned in August and ended up throwing just seven quality starts out of 19.

Giants manager Bruce Bochy and GM Brian Sabean have said that Vogelsong deserves the benefit of the doubt, not only because he has revived his career once before but also because he likely was set back by pitching in the World Baseball Classic last March, immediately after such a short offseason. As for Vogelsong, he has expressed a strong desire to return and work with pitching coaches Dave Righetti and Mark Gardner.

The club has two current vacancies in its rotation behind Matt Cain, Madison Bumgarner and Tim Lincecum.