Let’s leave Seranthony Dominguez in his current role (for now)

Corey Knebel has struggled of late. The blown save Tuesday night was the latest example where he was not able to get his job done, which have led to renewed calls for his removal as the team’s closer.

There is some logic to it, although some people may believe Knebel would lose the job for altogether different reasons.

Still, with the team trying to remain in the thick of the playoff chase (yes, it’s time to start thinking about it), there isn’t much more leash that can be let out with Knebel as the closer. Would he solve the team’s apparent 7th/8th inning issues, in a much less stressful environment? That’s a different question for a different time, but let’s focus on what some people see as the solution to the closer issue.

Leave Seranthony Dominguez right where he is and let someone else close.

Now, writing this on the heels of Dominguez allowing a game tying home run to Jazz Chisholm is probably not the wisest thing, but I believe we can all agree that he is allowed to have a wobbly outing now and then. Besides, the only wobbliness he has had of late was that home run; other than that, you can make the argument he has been their best reliever this season. He’s certainly been their most trusted.

Among all qualified relievers in the game, Dominguez’s 0.8 fWAR ranks 14th among them. With those same qualified relievers (189 of them), he also ranks 14th in strikeout rate (34.4%), tied for 42nd in home runs per nine innings (0.38) and 50th in groundball rate (50.9%). He’s been very good for the team in the role that they have carved out for him, one that puts him into the toughest spots they have during a game.

Therein lies the rub.

During this season, Knebel has the highest gmLI on the team at 1.72, which makes sense since they have used him in save situations most often. As a quick refresher, here is the official game leverage definition from Fangraphs:

The mechanics behind Leverage Index, however, are easy enough to follow. If you’re extremely interested, you should read this full explanation from Tom Tango, the creator of this flavor of LI. Leverage Index is essentially a measure of how critical a particular situation is. To calculate it, you are measuring the swing of the possible change in win expectancy. You take the current base-out state, inning, and score and you find the possible changes in Win Expectancy that could occur during this particular plate appearance. Then you multiple those potential changes by the odds of that potential change occurring, add them up, and divide by the average potential swing in WE to get the Leverage Index.

Right behind Knebel is Dominguez at 1.46. Dive a little further and we can find that Knebel has been brought into the game in the ninth inning in 22 of his 26 appearances this year. When he was brought into the eighth inning, it was twice when the team was losing and Joe Girardi wanted to keep the game close, and twice when he was called upon to get a multi-inning save.

Counter that with when Dominguez was being used. Since the team was regularly using Knebel for the end of game situations, Dominguez was most often called upon when the game was still in the balance. He has the best stuff on the staff (that can actually be controlled) so naturally the team would want him as the old school “fireman”. It’s something that a lot of modern front office have tried to acquire since that way of thinking has become prevalent around the game. It makes sense, too. If you have a big situation where you need outs and it’s only the seventh inning, why not use your best reliever when the game is in the balance right then?

That is why leaving Dominguez where he is at right now might make the most sense for the team. They have had struggles with their bullpen the past few years, legendary struggles some might say. We saw an example the other night of how a game can be lost earlier than in the ninth inning when Jeurys Familia came into a low leverage spot and promptly allowed the Marlins back into the game. It shouldn’t be lost on anyone that Dominguez did allow the tying run that inning, but had that home run he allowed been one that made the score 8-5 instead of 8-8, it would be looked at a little differently.

The way that Rob Thomson is going to run the closer’s job, one where the matchups determine the pitcher, is not a bad idea at all. If the next three batters up in the ninth are left handed hitters, maybe letting Brad Hand have a crack at it would be a better idea than Dominguez or Knebel having a run. But the team needs someone dependable in those middle innings when games are still close. Letting Dominguez have the bulk of those chances would greatly increase their odds of winning as opposed to having someone else take those turns.

Or they could always acquire another reliever.