How Well Has the Patriots' Offense Performed Without Rob Gronkowski?

The Patriots will play in Super Bowl LI without their biggest offensive asset. How have they fared without him?

The narrative around Tom Brady is that he plays well when he's ticked off. This dude must absolutely hate playing with Rob Gronkowski.

Any split you looked at heading into this year, it was clear that Brady performed better whenever Gronk was on the field.

For example, from Gronkowski's 2010 rookie season through 2015, Brady averaged 7.92 yards per attempt in games Gronk played compared to 6.67 without him, according to the RotoViz game splits app. We're talking full-on, uncontrollable rage whenever this physical specimen was healthy.

As Brady and the New England Patriots prepare for Super Bowl LI against the Atlanta Falcons, though, they don't have their spark plug of fury. The team placed Gronkowski on injured reserve after back surgery in December, prematurely ending his season.

Their offense has obviously been good enough to get all this way, but they're not at full strength with Gronk watching from the suites.

This Patriots team is different from the one they have rolled out in the past, though, meaning we need to see how they've performed in 2016 with and without Gronkowski to know how big of a loss this is.

We can get a good read on this using numberFire's Net Expected Points (NEP), the metric we use to track the efficiency of both teams and players with the team totals being adjusted for strength of opponent. Here, we'll be focusing on Passing NEP, which shows the expected points a quarterback gains or loses on each drop back, including all expected points lost on things such as sacks, incompletions, and interceptions.

This would be able to tell us the impact of Gronkowski's absence on this year's Patriots. And based on the data, they really miss their big man.

Significant Dip in Efficiency

We're going to limit the scope here to just the 12 games that Brady played in the regular season so as to not muddy the waters with Jacoby Brissett. In five of those games, Gronkowski played at least 50% of the snaps, giving us a decent sample on both sides.

Here are Brady's splits in the five games he had Gronk versus the seven he did not. Success Rate is the percentage of drop backs that result in positive NEP.

SplitDrop BacksPassing NEPPassing NEP/
Drop Back
Success Rate
With Gronkowski17689.380.5155.11%
Without Gronkowski27172.660.2748.71%

Whew, doggies. Them's some big splits.

Brady had more NEP in the 176 drop backs he had Gronkowski than he did in almost 100 additional drop backs without him. This is exactly what you'd expect given his track record without Gronkowski, but seeing his efficiency almost get cut in half is still startling.

Because these samples aren't necessarily robust, we could be seeing the effects of matchups. If the team played overly easy competition when Gronkowski was active, it would have an influence here. That was partially true, but it doesn't account for the full split.

In the five games the Patriots had both Gronkowski and Brady, they never faced a team ranked higher than 14th in Adjusted Defensive Passing NEP per play. Without Gronkowski, they did face the Denver Broncos, who led the league in this stat, but none of the other six teams were in the top 10. While schedule may have been a factor, it's not causing a chasm this big.

Based on this, we can definitively conclude that Gronkowski's injury was a big one, and it hurts the offense going forward. But the product they put out there after he went down was also pretty solid.

If we just look at Brady's Passing NEP per drop back without Gronk, he would have ranked third in the league among passers with at least 100 drop backs behind -- shocker -- Matt Ryan and Dak Prescott.

His mark with Gronkowski would have been the most efficient season in numberFire's databases, which go back to 2000. The takeaway here isn't that they're bad without Gronk; it's that they were other-worldly with him.

The Patriots have pieces in place to allow them to succeed even while Gronkowski recovers. Julian Edelman can handle a heavy dosage of targets, and Chris Hogan was one of the most efficient wide receivers in the entire league. Add in Dion Lewis and LeGarrette Blount, and you've got a really solid offense.

It's just hard not to wonder what they'd be doing if Gronkowski were healthy.

Looking Forward

In facing Atlanta, New England will go up against the league's 22nd-ranked pass defense. They've excelled against much tougher units this season, no matter who was able to play. Gronkowski's absence is still a big one.

With both Gronkowski and Brady, the offense hummed along like no other. If he were playing this week, then the Patriots could have posted a 50 burger on the Falcons. While that could still happen (he's Tom freaking Brady, after all), the odds would seem a wee bit lower without Gronk.

This is an awesome offense regardless of who's on the field. The Patriots have proven over and over that they can succeed while Gronkowski watches. But if the score winds up being close -- as it very well could -- the loss of the freakish tight end may be the key that prevents the Patriots from snagging yet another Lombardi Trophy.