He has previously played in MLB for the Texas Rangers, Arizona Diamondbacks, Seattle Mariners, Miami Marlins, and Toronto Blue Jays.

[6] de Geus signed with the Dodgers and made his professional debut in 2018 with the Ogden Raptors, going 4–5 with a 7.26 ERA over 15 games (14 starts).

[9] de Geus was a non-roster invite to 2020 spring training,[10] but he did not play in a game in 2020 due to the cancellation of the minor league season because of the COVID-19 pandemic.

[13] On April 1, 2021, de Geus made his major league debut, surrendering three earned runs in one inning pitched.

On June 22, 2022, de Geus signed with the York Revolution of the Atlantic League of Professional Baseball (ALPB).

On May 11, 2023, de Geus' contract was purchased by the Kansas City Royals and was assigned to the Triple-A Omaha Storm Chasers.

[20] In 29 appearances split between Omaha and the Double–A Northwest Arkansas Naturals, he accumulated a 4.86 ERA with 36 strikeouts across 46+1⁄3 innings pitched.

[26] On August 5, 2024, de Geus was claimed off waivers by the Miami Marlins and optioned to the Triple-A Jacksonville Jumbo Shrimp.