Right after the Trade Deadline, we ran some numbers which showed the Astros bullpen just might have been the worst of all time. Now that we are at the end of the season, we can't check to see whether it ended up that way or not.
To recap the previous post, we identified three primary contenders. The WAR and FIP- "leader," the 1966 NY Mets, the raw ERA and ERA- "leader," the 2007 Devil Rays and the raw performance SD/MD ratio leader, the 1999 Royals. At the time of the post, the Astros were right there with the Mets, but trailed the D-Rays and Royals in those categories.
In the month after the post, the Astros blew by the Mets in WAR. At their worst, I think they reached -5.9, clobbering the -4.5 post of the Mets. During the month of August, the Astros nearly-all-rookie relief core amassed a 5.71 ERA and a 5.12 FIP, with -1.2 WAR. It was looking like they were going to remove all doubt on whether they were the worst of all time. Then something interesting happened. They got a little better. In September, the relievers put up a 3.61 ERA, with 4.51 FIP and only -.2 WAR. The 15 game losing streak can't be pinned on them, as the last 14 days of the season, they were actually quite good, with a 3.09 ERA and a 3.37 FIP. Quite possibly for the first time all season, they were a net positive, posting .6 WAR during that stretch.
The finals numbers for the bullpen were a 4.92 ERA a 5.09 FIP, good for a 124 ERA- and a 129 FIP-. They totaled -5.4 WAR for the year. In regard to raw performance, they had 32 saves compared to 29 blown saves, and a SD/MD ratio of 104/88.
So how does that measure up? They are firmly established as the worst WAR leader, beating the Mets by -.9 WAR. However, a lot of that can be explained by the Astros throwing nearly 50 more innings. They were no match for the Mets' 136 FIP-, or the D Rays' 138 ERA-, and they avoided joining the Royals as one of the few teams with more blown saves than saves. Their SD/MD ratio was nearly the reverse of the Royals' 74/101 ratio as well.
At the end of the day (season) I think its fair to say the Astros might not have had the worst bullpen of all time, despite what WAR says. It might only be the second worst, or at best the third or fourth worst, depending on which measure you prefer. HUZZAH. Seriously, none of that suggests that this bullpen should not be blown up, and started from scratch.