5. Miles Mikolas signing (2017)
The Cardinals' most successful reclamation project from overseas in years, Miles Mikolas had a 2.18 ERA in Japan before the Cardinals took a flier on him before the 2018 season. He was a revelation in his first season back in the United States, finishing with an 18-4 record and a 2.83 ERA. He led the team in innings pitched, with 200.2, and he was voted to the All-Star team.
After he missed all of 2020 and part of 2021 with an injury, Mikolas returned to full strength in 2022 and delivered another productive season, pitching 202.1 innings with a 3.29 ERA, and he made it to the All-Star team again. The Cardinals signed him to a two-year extension that runs through 2025.
The Cardinals have gone back to Asia a few times since Mikolas' arrival in St. Louis to bring back former major leaguers who traveled across the Pacific Ocean, and while they whiffed with Aaron Brooks, Drew VerHagen has so far proven to be an adequate find.
Mikolas was able to translate his success in Japan to the major leagues, and he has been a fixture in the Cardinals' rotation for four full seasons. While his start to the 2023 season was less than ideal, Mikolas has begun to turn his performance around, and that extension could still be valuable with Steven Matz the only other starter under contract for 2024.