De San Miguel attended South Fremantle Senior High School in Perth, Western Australia before signing with the Minnesota Twins organization as an undrafted free agent on August 18, 2004.

[citation needed] On January 9, 2012, de San Miguel signed a minor league contract with the Baltimore Orioles following a strong showing in the ABL.

[citation needed] He spent the 2014 season as the starting catcher for the Southern Maryland Blue Crabs of the independent Atlantic League of Professional Baseball.

[citation needed] On January 12, 2015, de San Miguel returned to the Twins organization, but appeared in only 3 games for the Triple–A Rochester Red Wings before suffering an injury.

On February 11, 2016, de San Miguel signed a minor league contract with the Kansas City Royals, batting .187/.248/.264 in 30 games between the Triple–A Omaha Storm Chasers and Double–A Northwest Arkansas Naturals.

[1] On January 10, 2020, de San Miguel signed a new minor league deal with the Kansas City Royals and was assigned to Double–A Northwest Arkansas.

Records that belonged to de San Miguel when he retired following the 2019–20 Australian Baseball League season include games (386), plate appearances (1560), at-bats (1300), runs batted in (214), hit by pitch (39), as well as strikeouts (294), and grounded into double play (42).

De San Miguel went 0-for-3 with a strikeout against Korea, and replaced Matt Kennelly late in the game against the Netherlands, striking out in his only appearance.

[5] The Royals announced that they hired de San Miguel to their major league coaching staff as a strategist and bullpen catcher before the 2022 season.