Ten Best Closer Seasons

• Note 1: My methodology consisted of downloading the stats for every player I define as a closer (see note 3), and then paring it down based on the stats I felt to be important (namely, ERA, ERA+, WHIP, BA, and OPS+--not saves).  It's not an exact science, but it's what I thought worked best.
• Note 2: No pitcher was allowed more than one spot in the ranking.
• Note 3: I define a "closer" as a pitcher with more than 20 saves in a season.  Say what you want about the viability of the save statistic, but it's clearly a good way to track whether or not a pitcher was his team's closer for that season.  Without further ado, to the ranking...

1. Dennis Eckersley, 1990 (OAK): 48 SV/0.61 ERA/.616 WHIP

Eck won his Cy Young for his 1992 season, but 1990 was clearly his best, as well as the best season all-time by a closer.  Eck's ERA+ that year was 610--almost 100 points higher than Papelbon's 2006, which is the next highest among all closers.  While Eck's K/9 of 8.96 is perfectly great for a closer, what really makes this season stand out is his K/BB ratio: 18.25.  In fact, he only gave up four walks all year, one of which was intentional.  The only closing season with a higher K/BB than Eckersley's 1990 was his 1989, in which he posted a 18.33 mark.  In 1990, however, he dominated opposing batters, to the tune of an .160 AVG and .397 OPS against.  Eric Gagne's 2003 numbers are marginally better here, but it's not enough.  Based on Eck's ERA+ and K/BB dominance, I have to award his 1990 the best season all-time by a closer.

2. Eric Gagne, 2003 (LAD): 55 SV/1.20 ERA/.694 WHIP

Eric Gagne's 2003 was superb, and for a while it looked like he would go down as one of the best closers of all-time.  Obviously that was not to be, but we can still look at his 2003 for the masterwork it was and still is. While his ERA and ERA+ are a tad middling, relative to the rest of this list, his dominance over hitters can't be overstated.  In addition to his great WHIP, he had a .133 AVG and--no, this isn't a typo-- an OPS+ of 4.  In case it wasn't obvious, both of those register at the top of those statistics' leaderboards.  The reason that I gave the top slot to Eck was due to Gagne's inferior ERA numbers and WHIP, but it's not hard to make an argument for Gagne.  For his efforts in 2003, Gagne was rewarded with the Cy Young award, a rare feat for a relief pitcher.  Here, I'll award him the honor of having pitched the second best closer season of all-time.

3. Jonathan Papelbon, 2006 (BOS): 35 SV/0.92 ERA/.778 WHIP

After a fairly easy top two, here's where things start to get shaky.  Papelbon's 2006 ERA+ of 517 is the second highest of all-time, but his WHIP and AVG (.167) are relatively par for the course.  In the end, however, I decided to place a higher weight on the ERA, and gave him third place on this list.  His ERA of 0.92 during a hitter's era is magnificent.  His 9.88 K/9, while not outstanding, is still an excellent mark.  While this may be a controversial pick, I think Papelbon is well deserving of the third slot.  (Fun fact: 2006 was Papelbon's rookie season, though he finished second in the RoY voting to Justin Verlander.)

4. Rich Gossage, 1981 (NYY): 20 SV/0.77 ERA/.779 WHIP

One thing that I can't understand is how Rollie Fingers won both the Cy Young and MVP in 1981, while Gossage only finished 5th and 9th, respectively, in the voting for those awards.  True, those are good rankings, but look at Gossage's dominance: an ERA and ERA+ that are among the top three of all-time for closers and an AVG of .141.  My favorite stat from Gossage's 1981 season: he only allowed four extra-base hits (1 2B, 1 3B, 2 HR).  Lest you scoff at his 20 saves, there's a reason for it: the 1981 season was strike-shortened, and the leader (Fingers) only had 28 saves.

5. Mariano Rivera, 2008 (NYY): 39 SV/1.40 ERA/.670 WHIP

I originally had Mo at #3 but dropped him two places after re-examining his ERA.  Still, #5 is not bad at all.  What originally kept him afloat in the top-3 was his WHIP (seen above) and his K/BB, which was a godly 12.83.  His ERA+ of 319 is fairly low, so I was forced to drop him two spots.  His offense allowed (or lack thereof) is good enough to keep in the top five, however.

6. John Smoltz, 2003 (ATL): 45 SV/1.12 ERA/.874 WHIP

What to do with Smoltzie?  His ERA and K numbers are great, but his WHIP is fairly average for an "elite" closer, and batters hit a surprisingly high .204 off of him.  However, while most pitchers will either do well in K/9 or K/BB, Smoltz posted a 9.81 and 10.21, respectively.  Separately, they're good numbers; together, they're nothing short of spectacular.  This is another case where I had to prioritize certain statistics, and after much debate I decided that his 1.12 ERA and 385 ERA+ are good enough to merit sixth place.  

7. J.J. Putz, 2007 (SEA): 40 SV/1.38 ERA/.702 WHIP

While all of the first six seasons on this list are legendary, Putz' 2007 was very quietly great.  His ERA+ of 319 is still great, if not spectacular relative to other pitchers on this list, but his dominance over batters was great.  His 10.30 K/9 compares favorably to his peers on this list, as does his low WHIP and AVG (.153).  If you ask me tomorrow he might very well beat Smoltz, but for now Putz will have to content himself with 7th.

8. Takashi Saito, 2007 (LAD): 39 SV/1.40 ERA/.718 WHIP

Saito and Putz' 2007 seasons are very similar, from the numbers down to the fact that they're both massively overlooked.  Neither of them received any Cy Young votes, and only Putz received any MVP votes (one 4th, 8th, and 9th place vote).  Putz' 2007 was better that Saito's in terms of WHIP and K/BB, but Saito had a superior K/9 (10.91).  Besides that, however, they were basically tied in every meaningful category, and awarding them a tie for seventh place would seem reasonably fair.  Like in baseball, I do not believe in ties, and so I must give Saito ninth place.

9. Billy Wagner, 1999 (HOU): 39 SV/1.57 ERA/.782 WHIP

While Wagner's numbers don't look that outstanding, what makes this a truly great season is his offensive numbers: an AVG of .135 and an OPS+ of 10 show how dominant he was in 1999.  Additionally, his 14.95 K/9 mark is great by any comparison.  His undoing was his propensity for walks, which then led to runs, which gave him a higher ERA (as well as a fairly middling ERA+ of 287).  But boy, that .135 AVG....

10. Rollie Fingers, 1981 (MIL): 28 SV/1.04 ERA/.872 WHIP

Fingers' Cy Young campaign of 1981 (I still don't understand...) is similar to Smoltz' 2003, except Rollie's ERA+ and K ratios don't hold up as well..  While I may not agree with Fingers' 1981 hardware, I don't dispute that this was a great season.  His 1.04 ERA is fourth-lowest of all-time, and his 333 ERA+ is pretty good.  He only gets tenth place due to his uninspiring offensive numbers (a .198 AVG and an OPS+ of 50 are good, but not great), along with his less-than-stellar K numbers.  While I don't think his CY and MVP were totally deserved, his place in this ranking is well warranted.

Others worthy of consideration: Joe Nathan, 2006 (MIN); Robb Nen, 2000 (SF); B.J. Ryan, 2006 (TOR); and Bruce Sutter, 1977 (CHC).