St. Louis Cardinals: Letting Trevor Rosenthal go was a mistake

After six seasons with the St. Louis Cardinals, the front office granted Trevor Rosenthal his unconditional release.

Breaking into the majors in 2012, Trevor Rosenthal has been a valuable asset to the bullpen for the St. Louis Cardinals. While Rosenthal had a rocky 2016 season that featured a near 2.00 WHIP and 6.5 walks per nine, the Missouri native has been a good relief pitcher overall in his 328 career games.

This season was interesting for Rosenthal, as Seung-hwan Oh was coming off of an impressive first year in the majors. Combine that with Rosey’s horrendous 2016 campaign and there was no doubt on who would be the closer.

As the early season progressed, the tables turned quickly as Oh became the erratic one and Rosenthal became the lights out one. From April 10 to May 14, Rosenthal shined with 1.88 ERA and an opposing triple slash line of .189/.232/.245 while Oh had issues with his numbers being 2.89 and .260/.341/.452, respectively.

After his impressive start, Rosenthal would struggle and struggle badly. In 19 games from May 17 to July 1, Rosenthal had an ERA of 6.75 and opposing hitters had an on-base percentage of almost .400.

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From July 4 until season’s end Rosenthal would go back to his old self, sporting an ERA of 1.56 and holding opposing hitters to a triple slash line of .175/.235/.222. In that time span Rosenthal would rack up seven saves without blowing a single save opportunity having a 7:1 strikeout to walk ratio.

Taking a look at the current bullpen, it is not the prettiest sight. While John Mozeliak has said that a top priority will be a relief pitcher, it will take more than one good arm to clean things up.

Oh, Zach Duke, and Juan Nicasio are all free agents along with Rosenthal (now). Tyler Lyons and John Brebbia were impressive, but Brebbia’s 4.13 FIP is something to look at. Brett Cecil and Matt Bowman were okay, but not spectacular, although Cecil did better than a lot of people give him credit for.

With the closer’s spot wide open and the right-handed setup job open (Lyons absolutely should be the left-handed setup man), the St. Louis Cardinals find themselves needing at least two relievers.

Nicasio does want to return and of course guys such as Sam Tuivailala, Miguel Socolovich, and Ryan Sherriff will want a shot at the pen. Wade Davis and Greg Holland will arguably be the top two pitchers on the free agent market, but both are tied to draft pick compensation.

Next: The possibilities for the 2018 Bullpen

All of the above will make Trevor Rosenthal that much more valuable to a team because he is not being linked to a pick. If the Cardinals do decide they want him back, they might have to pay more than they want.