Bennett made his major league debut in 1995 for the Phillies on September 24 against the Cincinnati Reds as a pinch hitter.

He then signed free agent deals with the San Diego Padres for 2003 (where he eclipsed the 300 at-bat mark for the first time and set a career-high in RBI, with 42), Milwaukee Brewers for 2004, Washington Nationals for 2005, and St. Louis Cardinals for 2006.

He hit four home runs in the span of a week, including a walk-off grand slam against the Chicago Cubs on August 27, 2006.

[4] On December 13, 2007, Bennett was named in the Mitchell Report,[5] which detailed his illegal use of performance-enhancing substances such as human growth hormone.

Bennett finished the 2008 campaign with a disappointing .190 batting average with one home run and four RBI in only 10 games played.