Thornburg underwent Tommy John surgery this week, Bobby Nightengale of The Cincinnati Enquirer reports.
Thornburg saved 13 games while posting a 2.15 ERA for the Brewers back in 2016, but it's been a brutal few years for him since then. He's now undergoing his second major surgery in the last four seasons after going through thoracic outlet surgery back in 2017. He's been limited to just 49.2 innings over the last three years, struggling to a 6.16 ERA. The timing of his latest surgery means he'll miss the entirety of the 2021 season. While he should be ready to go around Opening Day of 2022, he'll be a 33-year-old at that point whose last good season came six years earlier.