He played in Major League Baseball (MLB) for the Toronto Blue Jays, Cleveland Indians, Tampa Bay Devil Rays, New York Yankees, Pittsburgh Pirates, and St. Louis Cardinals.

Phelps was also a member of the independent Bridgeport Bluefish, as well as the Telemarket Rimini of the Italian Baseball League.

Phelps attended Lakeland High School in Rathdrum, Idaho, where he was the baseball team's Most Valuable Player as a senior, and graduated 4th in his class in 1996 with a 3.94 GPA.

In November 2006, he signed with the Baltimore Orioles to a one-year minor league contract, but he was acquired by the Yankees in the Rule 5 Draft on December 7, 2006.

Initially picked to platoon at first base with Doug Mientkiewicz, manager Joe Torre hinted that Phelps might man the position by himself if his impressive spring training numbers continued into the regular season.

On November 29, 2007, he elected to file for free agency and was signed to a minor league contract by the St. Louis Cardinals on January 10, 2008.

On October 15, 2008, he was designated for assignment to make room for left-handed relief specialist, Charlie Manning.

[3] On November 3, 2008, the San Francisco Giants signed Josh Phelps to a minor league contract with a spring training invitation.