Pirates make necessary moves to improve bullpen, but GM Ben Cherington must do more

Santana emerged as one of the Pirates' most reliable relief pitchers a year ago, taking over the closer role following the trade of David Bednar to the New York Yankees at last year's trade deadline. Santana entered the season with a lock on that position, but rapidly began to lose the confidence of the coaching staff and front office due to his ineffective work on the mound.

It got so bad in recent weeks that he was basically being relegated to mop-up duty due to his inability to consistently get anybody out.

Marinaccio has had some brief moments of success in small samples sizes over the year, but he has struggled at times this season. But it's a change, and the big move from a Pirates perspective is getting rid of somebody who was simply not getting the job done.

It would, however, be unfair to put all of the blame on Santana. He has been only one struggling pitcher in a bullpen full of struggling pitchers. Manager Don Kelly doesn't really have anyone he can rely on in big moments right now, and it has resulted in the Pirates losing seven games this season where they had a win probability of 89% or higher with less than five outs to go in a game.

That includes three games with a win probability of 90% or higher in the ninth inning.

Those are the type of losses that you look back on in October with anger when you miss the playoffs by a game or two. The Pirates cannot afford many more of those, and they cannot afford to waste another season of Paul Skenes. Nor can they afford to waste this offense that is only going to get better on paper when currently injured stars like Oneil Cruz, Spencer Horwitz, Endy Rodriguez and Konnor Griffin start to return. 

That is why the moves on Thursday can only be the start of their bullpen overhaul. They still need a lot more. 

They do not just need one or two minor changes. They need multiple new arms they can trust, and basically a midseason overhaul of the bullpen.