The Mets can’t lose, and having won 11 straight games on their way to a 13-3 record, they own the best winning percentage in baseball. On Monday, I pointed out that we have to take them seriously as contenders because of this hot start, as those wins aren’t going to be stripped away in the future even when the Mets stop playing this well. But, while the wins-in-the-bank argument is still valid, there is a pretty decent counterpoint to that argument; the Mets have essentially been borrowing from their overall expected win total by playing a collection of lousy opponents so far.

Among the 16 games they’ve played this season, we find three against a depleted Nationals team that started the year with a Spring Training roster, six games against a Braves team that projects as one of the NL’s weakest squads, four games against a mediocre Marlins team that might be worse than expected, and three against the Phillies, everyone’s pick for the worst team in baseball. In addition, 10 of their 16 games have come at home, so while home field advantage isn’t a huge factor in baseball, they have gotten a slight bump from a disproportionately low number of road games.

So, yes, the Mets have been beneficiaries of a very easy schedule so far, but how much should we have expected them to win based on their opponents to date? This is actually something we can answer now, since we publish pre-game odds for every match-up in baseball on our scoreboard page. These odds take into account the actual line-up and starting pitcher for that day, so we’re also accounting for the fact that their games against the Nationals included match-ups with Max Scherzer, Stephen Strasburg, and Jordan Zimmermann; facing those guys is not the same thing as facing the Nationals when they’re throwing Doug Fister or Gio Gonzalez, with no disrespect intended to two quality pitchers who just aren’t quite at that level.

By looking at the difference between a team’s average game odds for the year and their expected rest-of-season winning percentage from Opening Day, we can get a decent idea of a team’s quality of opponents. So, with some assistance from Sean Dolinar, that’s exactly what I did, and the results can be seen in the graph below.

Teams above the line have had an easier schedule, teams below somewhat tougher.

The numbers confirm what we’d expect; playing a steady diet of the Marlins, Phillies, and Braves has indeed given the Mets the easiest schedule of any team in the big leagues to date; their average game odds have put them at an expected .535 winning percentage, up 30 points over their pre-season .505 mark. The other team who has seen a 30 point spike in their average game odds compared to their pre-season expected winning percentage? The 12-4 Royals, who have baseball’s second best record. It is not a coincidence that the two teams who have started the strongest have also played the softest schedules of any team in baseball; quality of opponent matters.

But again, what we really care about is the magnitude of the factor, and with a .535 expected winning percentage based on average game odds, the Mets are still trouncing their expected record. Having a weak slate of opponents would have suggested that we think the Mets should be 9-7 after this stretch, not 13-3. This isn’t the kind of variable that explains the entirety of the Mets success so far, and we can’t just wave away 13 wins in 16 games as the sole product of having played a weak schedule. The weak schedule explains just one of their extra five wins.

And it’s not like a slate of weak opponents is any kind of guarantee of success. Of note, check out the Brewers in that graph; they had a pre-season expected winning percentage of .481, but have had average game odds of exactly .500. When you look at their overall opponents — six against PIT, three each against STL, CIN, and COL — you might not think it was a relatively easy ride, but they got really lucky in their starting pitching match-ups against the Pirates: two starts each from Vance Worley and Jeff Locke, plus a call-up start by Casey Sadler, and then one tough game against Gerrit Cole.

Misisng both Liriano and Burnett makes those games against the Pirates easier match-ups than you might think, and Andrew McCutchen sat out one of the contests as well. The Reds and Rockies aren’t very good, so combine those seven games with easier-than-expected match-ups against the Pirates, and the Brewers have actually had a pretty easy go of things as well. And yet, even after getting a good draw to start the year, they’re 3-13, and their season is effectively over already. The Mets have taken advantage of weak opponents; the Brewers inability to win the games they’ve played suggests that they might be even worse off than we think.

Likewise, the Marlins (.500 pre-season expected record, .527 average game odds) have also benefited from playing the Braves and Phillies, at least theoretically, but they haven’t capitalized on those games the same way the Mets have. While people like to cite record versus winning teams as some kind of true barometer of roster quality, the reality is that playoff teams usually just pound bad teams into the ground, then try and hold their own against the decent or good teams. The Mets and Royals have done exactly what they needed to do thus far; beat the pants off of lousy opponents.

So, yes, the Mets have had an easy schedule. No, they don’t get to keep playing the Braves, Marlins, and Phillies all year, and they will find the road more difficult when they travel to face some better opponents. But the Mets low quality of opponents to date doesn’t cancel out the fact that they’ve played .812 baseball against a slate of games where we expected them to play .535 ball, and the difference between their current winning percentage and their game-odds expected winning percentage is still the largest in baseball. No team has outperformed expectations more than the Mets, even after you adjust for the fact that they’ve played the Marlins, Braves, and Phillies 13 times.