Kim Sa-rang was originally cast in the series, but backed out in February 2018 due to scheduling conflicts. She was replaced by Kim Min-jung.
The drama was first pitched by Studio Dragon to SBS, but the latter passed on the project due to financial and advertising constraints.
The series is the third collaboration between writer Kim Eun-sook and director Lee Eung-bok, after Descendants of the Sun (2016) and Sseulsseulhago Chalranhashin: Dokkaebi (2016).
This was originally planned in 2009 to be a sports-themed period drama set in the 1920s and 1930s, also featuring an American lead character. Woo-chul Shin, Kim Eun-sook's collaborator for the "Lovers" trilogy, was attached to be the director at the time.