Rosenthal was a standout reliever for most of his run with the Cardinals from 2012-17, during which he was a dominant closer at times. However, Rosenthal’s Cardinals career came to an unfortunate end when he underwent Tommy John surgery in August 2017. He sat out 2018 while rehabbing the injury, but Rosenthal parlayed his track record in St. Louis into a $7MM guarantee with the Nationals last November. The Nats still owe Rosenthal approximately $3.73MM.
Washington’s hope upon signing Rosenthal was that he’d help repair a bullpen that was among the league’s worst in 2018. Instead, Rosenthal became the poster boy for an even sorrier Nationals relief corps this season. The trouble began right away for the 29-year-old Rosenthal, who failed to record a single out until his fifth appearance of the season. After a couple more weeks of struggles, the Nationals sent Rosenthal to the injured list April 26 because of a viral infection.
Rosenthal finally returned from a rehab assignment June 10, but his long layoff didn’t lead to a rebirth. Fittingly, he didn’t get anyone out during his final Nationals appearance in a loss Saturday versus the Braves, who posted three earned runs on three walks against him. Rosenthal concluded his disastrous D.C. run with a 22.74 ERA and 7.11 K/9 against an unbelievable 21.32 BB/9 in 6 1/3 innings.
As woeful as Rosenthal has been this year, he still has his Cardinals days and a 98 mph fastball on which to hang his hat. Consequently, teams could pursue Rosenthal on a minor league contract in his return to free agency.