Trevor Rosenthal split the 2020 season between the Royals and Padres and he had an excellent season after signing with the Royals on a minor league deal with an invite to spring training last offseason. He pitched to a 1.90 ERA in 23 appearances between the two clubs with 11 saves, a FIP of 2.22, and an ERA+ of 240. His WHIP was 0.845 and he struck out 14.5 batters per nine innings compared to just three walks.
Joakim Soria, 37 in May, has been in the major leagues as a reliever going back to 2007 when he pitched for the Royals. He pitched for them through the 2011 season. His last two seasons there, his bullpen coach was none other than Steve Foster, the Rockies’ current pitching coach.
Recently, he is yet another reliever that has been a key figure in the Oakland A’s bullpen but will be a free agent this offseason. In the last three seasons between the A’s, White Sox, and Brewers, Soria has pitched to a 3.61 ERA (117 ERA+) in 159 games with a FIP of 3.05. His WHIP has been 1.105 and he has struck out 10.5 batters and walked 2.7 per nine innings.
Blake Treinen, who will be 33 next June, had a phenomenal season in 2018 for, you guessed it, the Oakland A’s. In fact, it was one of the best seasons ever posted by a reliever. However, after a down season with Oakland in 2019, they let him go and the Dodgers signed him for the 2020 season.
In 2020, he had a bit of a rebound season but nowhere good as his 2018 season. He had an ERA of 3.86 in 27 appearances in 2020 with a FIP of 3.15. His WHIP was 1.208 and he had a strikeout-to-walk ratio of 2.75:1.