Boston Red Sox: How does the rotation look now?

What else can we look at?

If you want to know how the difference between their ERA and FIP ranks in baseball, there’s always E-F. Here the Red Sox Rotation is 9th in baseball at 0.20, meaning only eight teams have a larger disparity. None of those teams are ahead of the Red Sox in any of the four metrics we’ve looked at so far. The Mets aren’t too far behind and do slot in with a slightly higher E-F at 0.30.

We can also look at the kinds of contact being allowed. Currently, the Red Sox have a 42.1% ground ball rate, 21st highest in baseball. So they are allowing plenty of fly balls. The good news is, few of them are line drives.

Their 18.5% line drive rate is the third lowest in the game. That matches up well with their league-leading soft contact percentage of 22.4%. So yes, they are allowing more balls in play in the air, but they aren’t allowing hard contact on them all that often.

That gets at the description in SIERA when discussing ground balls and how they lead to outs more than fly balls. If the contact in the air is of the soft variety, we’ll see plenty of outs there. And with three excellent defensive outfielders in Andrew Benintendi, Jackie Bradley Jr., and Mookie Betts, that will be true even on a fair amount of the hard contact.

And here’s the other thing. The Red Sox have the second lowest pull percentage in baseball at 39%. That’s important since it also fuels the lower hard contact rate on balls allowed in the air.

How do balls in play in the air break down league-wide?

So far this season, MLB has a 401 wRC+ on balls in the air to the pull side. That’s 301% better than league average. Allowing the other teams to put the ball in the air to the pull side is bad. Very bad. If we compare that to up the middle contact in the air, we see a 168 league-wide. Opposite field? Just a 95 wRC+.

So the Red Sox keeping hitters from going to the pull side is allowing them to succeed despite a higher rate of balls allowed in the air. It’s one of the reasons why their line drive rate is so low.

That’s a pretty good indication that what they are doing is sustainable. And if they can keep this up, they have as good a shot as anyone of succeeding in the playoffs. This isn’t the best rotation in baseball. Not even close.

Next: Sox names to look for in the 2018 MLB draft

But it does appear that warts and all, it is good enough for this team to win the division and make a run in the postseason. With the offense looking like one of the best in the game, it will come down to the bullpen. And while the pen may inspire more questions than the rotation does, that’s a look for another day.