Piatt played baseball at Bishop Verot High School,^[1] followed by a successful college career at Mississippi State University (MSU), helping lead the Bulldogs to multiple NCAA Tournament appearances. Piatt led the MSU team in 1996 with a .370 batting average. Piatt played mostly at third base for MSU and was named to the second team All-Southeastern Conference unit in 1997, when the Bulldogs reached the College World Series. He chose to leave school early after that, and signed a professional contract. Piatt finished his education at MSU, earning Cum Laude honors from MSU's Business School.

Piatt's best year was 1999 when he won the triple crown and minor league player of the year award at third base. He became an outfielder because of the A's present third baseman, Eric Chavez, and that was the only opening on the A's. He hit .299 in 60 games in 2000 with 5 home runs and 5 triples. In 2001, he got viral meningitis, but survived. He was designated for assignment by the A's in August 2003 and was claimed off waivers by Tampa Bay. In 2004, he went to Cleveland, but retired before the season.

Piatt was once featured in a commercial for K-Swiss shoes.^{[citation needed]}

In the Mitchell Report, Piatt admitted to having used steroids. Piatt said that former A's teammate F. P. Santangelo had told him about a man who could give Piatt human growth hormone (HGH). Piatt (who was trying to come back from viral meningitis) received HGH and testosterone from Kirk Radomski and used them in the 2002–2003 off-season. After using them, he said he "did not love the game when he used them" and that he had learned a life lesson. Piatt told all of this to Mitchell during their meeting. Former Senator George Mitchell commended Piatt for his honesty, and for being one of the few players to come forward to discuss the league's performance-enhancing drug use.^{[citation needed]}

Piatt now lives in Cape Coral, Florida.

• List of Major League Baseball players named in the Mitchell Report

• Career statistics and player information from Baseball Reference, or Fangraphs, or Baseball Reference (Minors), or Retrosheet