Isan Xavier Díaz (born May 27, 1996) is a Puerto Rican professional baseball second baseman for the Algodoneros de Unión Laguna of the Mexican League.

He has previously played in Major League Baseball (MLB) for the Miami Marlins, San Francisco Giants, and Detroit Tigers.

Díaz is originally from Puerto Rico, but his family moved to Springfield, Massachusetts, when he was four years old.

[9][10] On January 30, 2016, the Diamondbacks traded Díaz to the Milwaukee Brewers along with Chase Anderson, Aaron Hill, and cash considerations for Jean Segura and Tyler Wagner.

[11] Díaz spent the 2016 season with the Wisconsin Timber Rattlers of the Single–A Midwest League, where he hit .264 with a career high 20 home runs and 75 RBI in 135 games.

[17][18] On January 25, 2018, the Brewers traded Díaz to the Miami Marlins, along with Lewis Brinson, Monte Harrison and Jordan Yamamoto in exchange for Christian Yelich.

[33] After five games in the month of September, Díaz suffered a left groin strain and was placed on the 60-day injured list.

[34] Díaz began the 2021 MLB season at the Marlins alternative training site after losing the starting second baseman role to Jazz Chisholm.

[36] Díaz hit his first career grand slam on May 8, 2021, off Milwaukee Brewers reliever Patrick Weigel.

On April 30, 2022, the Marlins traded Díaz to the San Francisco Giants for a player to be named later or cash considerations.

[45] On August 7, 2023, Díaz was claimed off waivers by the Detroit Tigers and optioned to the Triple–A Toledo Mud Hens.