Since the Cubs Are Unstoppable, Who's the Second-Best Team in Major League Baseball?

Through about a quarter of the 2016 season, the Chicago Cubs have easily been the best team in baseball. They own a .737 win percentage and a +108 run differential.

Using numberFire’s nERD statistic -- which calculates the number of runs a team would win by against an average one -- the Cubs come out on top yet again, with a score of 2.60.

The Cubs are good. Very, very good.

But who's the next best team in Major League Baseball? Let's take a look at three possible squads.

Boston Red Sox

Why They’re Number Two: The Sox have played 41 games this season and own a 25-16 record, which is good for the third-best winning percentage in baseball. Also, they’re run-differential of +57 trails only the Cubs.

Boston has registered the second highest nERD score, at 1.76, and our algorithm gives them an 11.4% chance of winning the World Series, which is the second-best of all teams.

The Red Sox are led by their offense, which is the best in all of baseball.

Weakness: Boston’s team ERA is 4.22, which is the 13th worst in baseball. Specifically, their starting rotation’s ERA is even higher, at 4.74, which is the 11th worst. The good news is that the team's SIERRA is better, as they're more of a middle-of-the-road pitching team according to more advanced metrics. The team’s offense is incredible, but at some point, their rotation will need to be more productive.

St. Louis Cardinals

Why They’re Number Two: At first glance, the Cardinals’ 21-19 record through 40 games looks pretty mediocre. But they own the third-best run-differential in baseball at +49.

Also, St. Louis has registered a 1.54 nERD so far this season, which is the third-highest in baseball. Like Boston, the Cards have been led by a strong offense. They rank in the top three in several important categories.

Weakness: The Cardinals haven’t been able to translate their strong peripheral statistics into wins so far this season. For instance, St. Louis is just 10-11 at home this season after winning 55 games at Busch Stadium last season. Also, they’re just 2-5 in one-run games this season and 0-1 in extra inning games.

Washington Nationals

Why They’re Number Two: The Nats have a 24-16 record through their first 40 games, which translates to the fourth-highest winning percentage in baseball. Washington also owns the fourth-best run-differential at +40.

According to our algorithm, the Nationals have the third-highest chance of making the playoffs at 70.1%, and the fifth-best chance of winning it all at 6.9%.

The Nationals have found success this season from their pitching, unlike the other two teams on this list. They rank either first or second in several pitching categories.

Whether it’s Max Scherzer striking out 20 batters in a game, Stephen Strasburg's 6-0 record, or Gio Gonzalez's 1.86 ERA (which is bound to regress), the Nats’ rotation is stacked.

Weakness: In terms of nERD, Washington comes in with the seventh-best score in baseball at 0.96. Certainly not shabby, but not as high as Boston or St. Louis. Also, even with Bryce Harper having another historic season, the Nationals’ offense hasn’t been very good -- their wRC+ of 91 is the 10th-lowest in baseball and their run total of 168 is the 13th-lowest.

Who's Ranked Second?

Led by their offense, the Boston Red Sox look to be the second-best team in baseball so far this season. They rank second in nERD and run-differential, and have the second-best chance of winning the World Series.

The Cardinals and Nationals aren’t far behind, though. It’s only a matter of time before St. Louis’ production translates to wins, and Washington’s pitching has been dominant.

A potential Cubs-Red Sox World Series sounds very entertaining at this point in the season, doesn't it?