There are changes coming to the 2019 Red Sox Bullpen.  Two big pieces, closer Craig Kimbrel and Joe Kelly, are both free agents.  Who is worth paying to keep and what are some options out there?

Today is the beginning of our deep dive into those questions.  We start with Joe Kelly.

Joe Kelly

Kelly had an indelible stamp on the 2018 team.  He started the year by blowing game 1.  He became Jim Buchanon and started a Joe Kelly Fight Club faze when he called out Tyler Austin of the Yankees.  Then he became an afterthought and albatross around the neck of the bullpen as the summer dragged on.

But then, in the playoffs, the mid-bullpen became a strength, because he became a strength.  In six innings in the World Series he had a 0.00 ERA and 10 strikeouts.  That is domination.

However, is that the Joe Kelly we know for any other stretch of time?  His ERA over the past three years has been 4.12 during the regular season.  His fastball has averaged 97.8 MPH over that same time.  How is that?

It has been noted frequently that his fastball is straight, and he could not get his breaking ball over for strikes.  This lead to walks, a lot of them.  Almost 5 per 9 innings, 4.67 to be exact.

It feels like instead of only relying on his gifted arm that can throw gas with ease, he finally starting pitching in this postseason.  Because he threw his breaking ball for strikes, it was almost that simple.

It’s at least a question whether he can repeat it.  Will he continue to work after winning the World Series?  Is he worth betting on?  History says no.  How about an alternative?

David Robertson

One name is David Robertson.  He has spent the past year and a half toiling in the mid to late innings for the New York Yankees.  Before that he was the Chicago White Sox closer.  Unlike Craig Kimbrel, Robertson has proven he can work in different innings and different game situations.

He throws a lot softer than Joe Kelly, averaging 91.9 MPH over the same 3 year period.  But his ERA weighs in at 2.85, about 30% better than Kelly.   He also strikes out 25% more batters.  How can this be?

Because he throws more strikes, and he pitches rather than throws.  He walks a batter less than Kelly.  Less runners on base leads to fewer runs allowed.

Conclusion

It’s not perfect.  Robertson still walks 3.7 per 9 innings, that’s high for a reliever.  Robertson is also 3 years older than Kelly.

But Kelly was not given the 8th inning with a lead until game 5 of the World Series.  This was not an accident, Cora didn’t trust him there.  Robertson can work the 6th, 7th, 8th, 9th, whatever you want.

Robertson will command north of what he’s making now, $13 Million per year.  Kelly probably much less.  But a team could bid up Kelly and make him expensive.

The choice here is Robertson, if you can convince him.  He’s representing himself in free agent negotiations and probably looking for closing opportunities.

The Red Sox might have an opening at closer.  More on that tomorrow.