Diaz elected to become a free agent Tuesday, Rich Dubroff of BaltimoreBaseball.com reports.
Diaz is a career .181/.227/.340 hitter in 343 plate appearances at the MLB level, but he posted a decent .804 OPS with 17 homers and 64 RBI over 118 games this past season with the Triple-A affiliate of the Orioles. The 26-year-old first baseman should be able to find a new organization this winter.