An era well and truly came to an end this week with the news that New England Patriots tight end Rob Gronkowski has retired from the NFL after nine seasons. Gronkowski has decided to bow out of the league after totaling 521 receptions, 7,861 yards and 79 touchdowns in 115 regular season games. In NFL history, only two tight ends -- Tony Gonzalez and Antonio Gates -- have reached the end zone more times in the regular season

Despite his dominance, the wear and tear began to show in Gronk's game. In 2018, he had 682 receiving yards in 13 games, along with three touchdowns. This was his lowest yardage in a season in which he played at least 10 games going all the way back to his rookie season. Only once prior to 2018 did he score so few times, and that was back in 2016 when he only played in eight contests.

With Gronkowski, the debate will now turn to whether his dominance warrants a place in the Pro Football Hall of Fame (it’s not a debate, in this author's opinion). But for the Patriots, the loss of Gronkowski leaves quite a hole.

Here, we will look at how they stand to replace the production of Gronkowski, and what that might mean for potential fantasy football assets in 2019.

The Gronk Effect

Having Tom Brady as your quarterback can be quite a boon for a player’s production. It may have escaped few people’s attention over the last two decades, but Brady is OK at playing the quarterback position in the NFL. So it is a testament to Gronkowski's greatness as we see the dip in Brady’s production when his stud tight end has been out of the lineup.

From 2010 to 2017, the splits are quite striking.

As we’ve previously touched upon, 2018 wasn’t a banner year for Gronkowski. The same must be said of Brady, who was just a rung below his usual levels of excellence in yet another Super Bowl season. Even with a decreased reliance on Gronkowski last season, his absence was still felt in Brady’s statistical decline.

With the loss of Gronkowski, Brady and the Pats have lost one truly outstanding playmaker. Brady’s days as a winner will probably continue, even as he keeps aging. But his days as a fantasy stud may have passed into the same sunset as that which Gronkowski is now riding off into. Brady finished outside the top 12 in weekly quarterback scoring 10 times in 2018; he did so just five times in the year prior.

Picking Up the Slack

The Patriots tried to bring in reinforcements during the early days of free agency, being strongly linked to wide receiver Adam Humphries and tight Jared Cook. The latter's signing with the New Orleans Saints could be doubly damaging to the Patriots after the Gronkowski news. The Patriots' pass-catching corps is already sans Gronkowski, and at this time one of their better weapons isn't currently on the roster.

Chris Hogan was actually the Patriots' most efficient wide receiver in 2018 (not counting Josh Gordon, in whom it is difficult to place any long-term trust) -- at least according to our metrics. Hogan posted 0.85 Reception Net Expected Points (NEP) per target last season, the 18th-most among the 84 wide receivers with at least 50 targets last season (You can learn more about NEP by checking out our glossary). By comparison, Julian Edelman posted 0.69. Hogan is still out on the street, but there is a chance he could return to the team.

Without knowing what the Patriots have in mind for the draft, in the absence of Gronkowski the responsibility would seem to fall on Edelman and pass-catching back James White. They may well be up to the task, considering how they have fared in games without Gronk up to this point (not counting the 2018 season).

However, it would be foolish to assume that the loss of Gronkowski is going to catapult either of these players into fantasy superstardom. Edelman will be 33 when the season starts and has played all 16 games of a season once since 2014. He began the 2018 season on the side-lines with a four game suspension for a PED violation, and has had more than 1,056 receiving yards in a season once. He is a free agent following the 2019 season,however, so maybe the Patriots will look to get as much out of him now as they can before moving on.

As for White, he has been one of the most productive pass catching running backs of the last three seasons. White's 248 receptions are the third-most among all running backs since 2014. He also has the fourth=most receiving yards with 2,164.

But while he has been pulling his weight in PPR formats, I find it unlikely that he will inherit much more work than he is already dealing with from a reception point of view. He did see the second most targets among RBs in 2018, after all. Given the lessening of Gronkowski’s load last year, I’d expect these two to see a slight uptick in work, while the remainder will be split among the ancillary pieces on the Patriots roster. Assuming the roster remains the same as it is today -- which it won’t be.

Ground and Pound

It is possible, however, that the biggest winner in the wake of the Gronkowski retirement may not be a receiver at all. It could be running back Sony Michel. Not that I'm suggesting that Michel suddenly emerges as a weapon in the passing game. Michel had a grand total of seven receptions as a rookie, after all. But the Patriots could look to lean on the ground game, and by definition Michel.

There were suggestions that this was the way the team wanted to go last season. The Patriots were third in total rushing attempts with 478, and had the eighth lowest pass to run ratio of 1.24. They were also bloody good when they ran the ball, posting the sixth best Adjusting Rushing NEP per play in the NFL with 0.08.

The Patriots have only had a lower pass to run ratio once in the four seasons prior to 2018. That was back in 2016, when they had a 1.19. They finished third in the NFL in rush attempts that season with 482. Why is this significant, you ask? Well, that was the last season that they didn't have Gronkowski healthy for the majority of the campaign. He played only eight games that season.

The Patriots' efficiency as a running team, allied to their usually being among the league leaders in total plays, would give Michel considerable value even without a strong pass-catching profile. The Patriots were second in total plays last season with 1,073. Michel could also benefit by increased usage in the scoring areas. He had 10 carries from the goal line last season, while Gronkowski saw seven targets inside the end zone (as per PlayerProfiler). If those targets were to become Michel, double-digit touchdowns are not out of the question for the sophomore back.

Here Comes the Cavalry

As previously mentioned, the Patriots' roster will not look the way it does today when the 2019 NFL season actually starts. There are still free agents that could be signed, while there is also the small matter of the NFL Draft coming up. There are a number of intriguing tight end options in this class, notably a pair of Iowa Hawkeyes -- Noah Fant and T.J. Hockenson.

Fant is an athletic freak who blew up the Scouting Combine earlier this offseason, but there are some who have questioned his blocking ability. Say what you like about Gronkowski, but he was a tremendous blocker, skills he showcased during his final postseason run with the Patriots. This would seem to disqualify Fant from gaining serious attention from the Patriots, although it is doubtful he'll be on the board by the time the Patriots come to make their first pick.

Fant's college teammate Hockenson is a player that the Patriots could have serious interest in. Dane Brugler notes that he has a complete skillset, making him a weapon as a pass catcher and a run blocker. A lot of mock drafts have Hockenson off the board early as well, just like Fant (although in his most recent mock draft, NFL.com's Daniel Jeremiah has him falling to the Houston Texans at 23). But the Patriots and Bill Belichick have never been afraid to gamble when it comes to the draft, like the time they spent a second-round draft pick on a tight end who missed his last season in college and fell due to concerns about his long-term health.

Anyone remember that guy? Oh yes, his name was Rob Gronkowski.

Conclusion

There is no end to the number of contenders jockeying to fill the void left by Gronkowski. However, given the Patriots' chameleon-like nature, it is hard -- if not impossible -- to accurately predict how the team will look to replace the production lost due to the end of a dominant era.

Gronkowski averaged 15.52 PPR points per game in his career and is one of only four Patriots players since 2001 to to do this. The other three are Randy Moss, Wes Welker and Corey Dillon. In the absence of genuine superstar talent, the Patriots are likely to spread the wealth pretty far and wide. There is a good chance that everyone gets a bump in fantasy production.

But will a new superstar emerge to replace Gronkowski? I wouldn't bet on it.