Astros decline $4 million option on C Chris Snyder
The 31-year-old Snyder, who gets a $500,000 buyout, played 76 games for Houston in 2012 and hit .176 with seven homers and 24 RBIs.
He batted .271 with three homers and 17 RBIs in 34 games for Pittsburgh before season-ending surgery on his lower back in June 2011.
Snyder played for Arizona from 2004 until joining the Pirates in 2010. He has 77 homers, 297 RBIs and a .225 average in his big league career.
In other moves Thursday, the Astros claimed right-hander Sam Demel and infielder Jake Elmore off waivers from Arizona. Left-handers Fernando Abad and Sergio Escalona, right-handers Edgar Gonzalez, Jose Valdez and Kyle Weiland, and infielder Matt Downs were sent outright to Triple-A Oklahoma City.
Abad, Downs, Escalona, Gonzalez and Valdez all became free agents.