Sometimes it seems as though the Toronto Blue Jays relievers get cast behind the explosive offense and dominant starting pitching of late of that of their teammates. But the Blue Jays relief corps are one of the best in the league. So how good are they?

Their ERA on the year is 3.15, which is very good in and of itself, but only puts them 7th in the team rankings. But while ERA is without a doubt the most popular metric for measuring a pitcher’s performance, it is highly dependent on defense, luck, and sequencing, and therefore tells you very little useful information about a pitcher.

With advanced statistics, we can portray a more accurate picture of how good a pitching performance has been by controlling for league, park factors, defense, HR/FB, etc.

Fielding Independent Pitching, or FIP, is a statistic that attempts to calculate a pitcher’s actual run prevention independent of their defense. The Blue Jays relievers’ FIP for the year is 3.48, putting them in 8th place in the league. So using this metric, they actually are a bit lower than what their ERA says, which isn’t a surprise if you know about the Blue Jays’ stellar defense.

And that’s where xFIP comes in. xFIP simply takes the FIP metric and replaces a pitcher’s home run total with an estimate of how many home runs they should have allowed given the number of fly balls they surrendered while assuming a league average home run to fly ball percentage (between 9 and 10% depending on the year). Since home run rates are not typically very stable over time, this means that there is an awful lot of random noise involved. So the “x” in xFIP is there to, again, try to more accurately control for luck and focus solely on pitching performance. The Blue Jays relievers xFIP for the year is 3.47, tied for second with the Astros and just behind the Brewers. Now we’re talking!

But there’s one more tweak we can make to xFIP and that is to control it for park and league factors. Major League ballparks vary widely in dimensions, altitude (I’m looking at you Coors Field), and even weather, so each ballpark has a Park Factor number that tries to offset pitching in favorable or unfavorable environments. 100 is seen as the “average” park, and the Blue Jays have a 102 Park Factor number, which means it’s a bit harder for a pitcher to put up good numbers at the SkyDome. It’s also a good idea to control for which league the pitcher is a part of since the AL has a DH and the NL does not, making AL pitchers’ numbers slightly higher since they don’t get to pitch to opposing pitchers often, which are generally the worst hitters in the lineup (someone should let Madison Bumgarner know). And so with all that adjusted, we have xFIP-.

Why is xFIP- so important? Because it has one of the highest correlations with future ERA of all the pitching metrics. And the Blue Jays relievers xFIP- is 87, which puts them in…drum roll please…

FIRST PLACE FOR THE YEAR!

Well, technically tied for first place with the Astros, but it’s still first, and it still means that no team in the Majors has a better xFIP- from their relievers than the Toronto Blue Jays.