[5] In 2015, he pitched in 23 games (21 starts) between the Great Lakes Loons and the Rancho Cucamonga Quakes and had an 8–5 record and 2.65 ERA.

[5] For the 2016 season, he pitched in four games for the Quakes, and 10 each for the Tulsa Drillers and Oklahoma City Dodgers, with a 14–3 record and 2.74 ERA.

[7] On January 4, 2018, Oaks was traded to the Kansas City Royals in a three-team trade that also sent Jake Peter and Scott Alexander to the Dodgers, Joakim Soria and Luis Avilán to the Chicago White Sox, and Erick Mejia to the Royals.

[8] He was recalled by the Royals on April 28, 2018, to make his major league debut as the starting pitcher against the White Sox.

In an interview on January 31, 2022, Oaks acknowledged that he had retired from professional baseball since his release from the Giants organization.