[2] He spent the first eight years of his MLB career with the San Francisco Giants (2000–2007), before signing a free agent contract with the Philadelphia Phillies, in 2008.

Although Feliz was a decent power hitter, his career batting average prior to the 2006 season was only .255, and he seldom walked, as evidenced by his on-base percentage (OBP) never surpassing the .305 mark, and his OPS never exceeding .793.

On June 8, 2007, in a game against the Oakland Athletics, Feliz played catcher for the first time in his major league career.

In 2008, struggling with an inflamed lower back, Feliz's power declined from previous seasons,[8] but on October 29, 2008, he delivered one of the most important base hits in Phillies history, when he knocked in Eric Bruntlett, to plate the winning run, in Philadelphia's Game 5, World Series-clinching win over the Tampa Bay Rays.

[9] On November 8, 2009, Philadelphia management declined to exercise Feliz's option for the 2010 season, thereby making him a free agent, once again.

[10] On August 19, 2010, the Astros traded Feliz to the St. Louis Cardinals, in exchange for cash considerations and pitcher David Carpenter.

On February 3, 2011, Feliz was signed to a Minor League Baseball (MiLB) deal by the Kansas City Royals, with an invitation to Spring Training.